MPLS Traffic Engineering—DiffServ Aware

(DS-TE)

This guide presents extensions made to Multiprotocol Label Switching Traffic Engineering (MPLS TE)
that make it DiffServ aware. Specifically, the bandwidth reservable on each link for constraint-based
routing (CBR) purposes can now be managed through at least two bandwidth pools: a global pool (also
called BC0) and a sub-pool (also called BC1). The sub-pool can be limited to a smaller portion of the
link bandwidth. Tunnels using the sub-pool bandwidth can then be used in conjunction with MPLS
Quality of Service (QoS) mechanisms to deliver guaranteed bandwidth services end-to-end across the
network.
Beginning with Cisco IOS Release 12.2(33)SRB, DS-TE has been augmented to conform to IETF
standards that were developed after the initial creation of Cisco DS-TE. Now both the traditional and the
IETF versions of DS-TE can be run on your network; the new releases are backwards compatible.

Feature History

Release Modification
12.0(11) ST DS-TE feature introduced.
12.0(14) ST Support was added for Cisco Series 7500(VIP) platform.
Support was added for IS-IS Interior Gateway Protocol.
12.0(14) ST-1 Support was added for guaranteed bandwidth service directed to many destination
prefixes (for example, guaranteed bandwidth service destined to an autonomous
system or to a BGP community).
12.0(22)S Feature was implemented in Cisco IOS Release 12.0(22)S.
12.2(14)S Feature was integrated into Cisco IOS Release 12.2(14)S.
12.2(18)S Feature was implemented in Cisco IOS Release 12.2(18)S.
12.2(18)SXD Feature was implemented in Cisco IOS Release 12.2(18)SXD.
12.2(28)SB Feature was implemented in Cisco IOS Release 12.2(28)SB.
12.2(33)SRB Feature was augmented to include the new IETF-Standard functionality of DS-TE,
as described in RFCs 3270, 4124, 4125, and 4127.

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Cisco Systems, Inc., 170 West Tasman Drive, San Jose, CA 95134-1706 USA
© 2007 Cisco Systems, Inc. All rights reserved.
 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Background and Overview

Finding Support Information for Platforms and Cisco IOS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image
support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on
Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at
the login dialog box and follow the instructions that appear.

The guide contains the following sections:

• Background and Overview, page 2
• Supported Standards, page 5
• Prerequisites, page 6
• Configuration Tasks, page 6
• Configuration Examples, page 13
• Command Reference, page 39
• Glossary, page 49

Background and Overview

MPLS traffic engineering allows constraint-based routing (CBR) of IP traffic. One of the constraints
satisfied by CBR is the availability of required bandwidth over a selected path. DiffServ-aware Traffic
Engineering extends MPLS traffic engineering to enable you to perform constraint-based routing of
“guaranteed” traffic, which satisfies a more restrictive bandwidth constraint than that satisfied by CBR
for regular traffic. The more restrictive bandwidth is termed a sub-pool, while the regular TE tunnel
bandwidth is called the global pool. (The sub-pool is a portion of the global pool. In the new
IETF-Standard, the global pool is called BC0 and the sub-pool is called BC1. These are two of an
eventually available eight Class Types). This ability to satisfy a more restrictive bandwidth constraint
translates into an ability to achieve higher Quality of Service performance in terms of delay, jitter, or
loss for the guaranteed traffic.
For example, DS-TE can be used to ensure that traffic is routed over the network so that, on every link,
there is never more than 40 per cent (or any assigned percentage) of the link capacity of guaranteed
traffic (for example, voice), while there can be up to 100 per cent of the link capacity of regular traffic.
Assuming that QoS mechanisms are also used on every link to queue guaranteed traffic separately from
regular traffic, it then becomes possible to enforce separate “overbooking” ratios for guaranteed and
regular traffic. In fact, for the guaranteed traffic it becomes possible to enforce no overbooking at all—or
even an underbooking—so that very high QoS can be achieved end-to-end for that traffic, even while for
the regular traffic a significant overbooking continues to be enforced.
Also, through the ability to enforce a maximum percentage of guaranteed traffic on any link, the network
administrator can directly control the end-to-end QoS performance parameters without having to rely on
over-engineering or on expected shortest path routing behavior. This is essential for transport of
applications that have very high QoS requirements such as real-time voice, virtual IP leased line, and
bandwidth trading, where over-engineering cannot be assumed everywhere in the network.

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MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Background and Overview

The new IETF-Standard functionality of DS-TE expands the means for allocating constrained bandwidth
into two distinct models, called the “Russian Dolls Model” and the “Maximum Allocation Model”. They
differ from each other as follows:

Table 1 Bandwidth Constraint Model Capabilities

Achieves
Ensures Isolation across Class Protects against QoS
Bandwidth
Types Degradation...
MODEL Efficiency

When When ...of the Premi- ...of all other

Preemption is Preemption is um Class Type Class Types
Not Used Used

Maximum Yes Yes Yes Yes No

Allocation

Russian Yes No Yes Yes Yes

Dolls

Therefore in practice, a Network Administrator might prefer to use:

• the Maximum Allocation Model when s/he needs to ensure isolation across all Class Types without
having to use pre-emption, and s/he can afford to risk some QoS degradation of Class Types other
than the Premium Class.
• the Russian Dolls Model when s/he needs to prevent QoS degradation of all Class Types and can
impose pre-emption.

DS-TE involves extending OSPF (Open Shortest Path First routing protocol), so that the available
sub-pool or class-type bandwidth at each preemption level is advertised in addition to the available
global pool bandwidth at each preemption level. And DS-TE modifies constraint-based routing to take
this more complex advertised information into account during path computation.

With the addition of IETF-Standard functionality (beginning with Cisco IOS Release 12.2(33)SRB),
networks may accomplish DS-TE in three different combinations or “modes”, so that they may transition
to the IETF-Standard formats in a manner that will not degrade their ongoing traffic service. These three
situations or modes are summarized as follows:
1. The original, or “Traditional” (pre-IETF-Standard) mode. This describes networks that
already operate the form of DS-TE that was introduced by Cisco a few years ago. Such networks
can continue to operate is this traditional mode, even when they use the new Release
12.2(33)SRB and subsequent releases.
2. The “Migration” or combination mode. Networks already running traditional DS-TE that
would like to upgrade to the IETF-Standard should first configure their routers into the
Migration mode. This will allow them to continue to operate DS-TE without tunnels being torn
down. In Migration mode, routers will continue to generate IGP and tunnel signalling as in the
Traditional form, but now these routers will add TE-class mapping and will accept
advertisement in both the Traditional and the new IETF-Standard formats.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Background and Overview

3. The “Liberal IETF” mode. Networks already running in the Migration mode can then move
into IETF formats by reconfiguring their routers into this flexible (hence “Liberal”)
combination: their routers will henceforth generate IGP advertisement and tunnel signalling
according to the new IETF Standard, but they will remain capable of accepting advertisement
in the Traditional format, as well as in the new IETF format.
Table 2 summarizes these distinctions among the three modes.

Table 2 Summary of DS-TE Mode behaviors

Uses
TE-class Generates Processes
mapping

MODE IGP RSVP-TE IGP RSVP-TE

Advertisement Signalling Advertisement Signalling

Traditional No traditional traditional traditional1 traditional

traditional & traditional &

Migration Yes traditional traditional
IETF IETF

traditional & traditional & traditional &

Liberal IETF Yes IETF
IETF IETF IETF

1Note that it is not possible for the Traditional mode to be liberal in what it accepts in terms of IGP, since it does not use TE-Class
mapping and therefore cannot interpret the “Unreserved Bandwidth” in the IETF-compliant way when the Subpool Sub-TLV
is absent.

Benefits
DiffServ-aware Traffic Engineering enables service providers to perform separate admission control and
separate route computation for discrete subsets of traffic (for example, voice and data traffic).
Therefore, by combining DS-TE with other IOS features such as QoS, the service provider can:
• Develop QoS services for end customers based on signaled rather than provisioned QoS
• Build the higher-revenue generating “strict-commitment” QoS services, without over-provisioning
• Offer virtual IP leased-line, Layer 2 service emulation, and point-to-point guaranteed bandwidth
services including voice-trunking
• Enjoy the scalability properties offered by MPLS.

Related Features and Technologies

The DS-TE feature is related to OSPF, IS-IS, RSVP (Resource reSerVation Protocol), QoS, and MPLS
traffic engineering. Cisco documentation for all of these features is listed in the next section.

Related Documents
For OSPF:

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MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Supported Standards

• “Configuring OSPF” in Cisco IOS IP Routing Protocols Configuration Guide, Release 12.4
• “OSPF Commands” in Cisco IOS IP Routing Protocols Command Reference, Release 12.4

For IS-IS:
• “Configuring Integrated IS-IS” in Cisco IOS IP Routing Protocols Configuration Guide, Release
12.4
• “IS-IS Commands” in Cisco IOS IP Routing Protocols Command Reference, Release 12.4

For RSVP:
• “Configuring RSVP” in “Part 5: Signalling” of Cisco IOS Quality of Service Solutions
Configuration Guide, Release 12.4
• “ip rsvp . . .” commands in Quality of Service Solutions Command Reference, Release 12.4

For QoS:
• Cisco IOS Quality of Service Solutions Configuration Guide, Release 12.4
• Cisco IOS Quality of Service Solutions Command Reference, Release 12.4

For MPLS Traffic Engineering:

• “Configuring MPLS Traffic Engineering” within “Configuring Multiprotocol Label Switching” in
Cisco IOS Multiprotocol Label Switching Configuration Guide, Release 12.4
• Cisco IOS Multiprotocol Label Switching Command Reference, Release 12.4

Supported Standards
The traditional (pre-IETF Standard) version of DiffServ-aware MPLS Traffic Engineering conforms to
the descriptions given in the following two documents:
• Requirements for Support of Diff-Serv-aware MPLS Traffic Engineering by F. Le Faucheur, T.
Nadeau, A. Chiu, W. Townsend, D. Skalecki & M. Tatham
• Protocol Extensions for Support of Diff-Serv-aware MPLS Traffic Engineering by F. Le Faucheur,
T. Nadeau, J. Boyle, K. Kompella, W. Townsend & D. Skalecki.
The IETF Standard for DiffServ-aware MPLS Traffic Engineering is described in the following four
documents:
• Multi-Protocol Label Switching (MPLS) Support of Differentiated Services by F. Le Faucheur, L.
Wu, B. Davie, P. Vaananen, R. Krishnan, P. Cheval, & J. Heinanen (RFC 3270)
• Protocol Extensions for Support of Diffserv-aware MPLS Traffic Engineering ed. by F. Le Faucheur
(RFC 4124)
• Russian Dolls Bandwidth Constraints Model for Diffserv-aware MPLS Traffic Engineering ed. by F.
Le Faucheur (RFC 4127)
• Maximum Allocation Bandwidth Constraints Model for Diffserv-aware MPLS Traffic Engineering
by F. Le Faucheur & W. Lai (RFC 4125).

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Prerequisites

The new concept of "Class-Type" defined in the IETF Standard corresponds to the prior concept of
“bandwidth pool” that was implemented in the original version of DS-TE. Likewise, the two bandwidth
pools implemented in the original version of DS-TE (global pool and sub-pool) correspond to two of the
IETF Standard’s new Class-Types (Class-Type 0 and Class-Type 1, respectively).

Prerequisites
Your network must support the following Cisco IOS features in order to support guaranteed bandwidth
services based on DiffServ-aware Traffic Engineering:
• MPLS
• IP Cisco Express Forwarding (CEF)
• OSPF or ISIS
• RSVP-TE
• QoS

Configuration Tasks
This section presents the minimum set of commands you need to implement the DiffServ-aware Traffic
Engineering feature—in other words, to establish a tunnel that reserves bandwidth to a sub-pool
(renamed BC1 by the IETF-Standard).
The subsequent “Configuration Examples” section (page 13), presents these same commands in context
and shows how, by combining them with QoS commands, you can build guaranteed bandwidth services.

From Traditional to IETF-Standard Commands

DS-TE commands originally were developed from the then-existing command set that had been used to
configure MPLS traffic engineering. The only difference introduced at that time to create DS-TE was
the expansion of two commands:
• ip rsvp bandwidth was expanded to configure the size of the sub-pool on every link.
• tunnel mpls traffic-eng bandwidth was expanded to enable a TE tunnel to reserve bandwidth from
the sub-pool.

The ip rsvp bandwidth command

The early MPLS command had been
ip rsvp bandwidth x y

where x = the size of the only possible pool, and y = the size of a single traffic flow (ignored by traffic
engineering).

Then, to create the original implementation of DS-TE, the command was made into
ip rsvp bandwidth x y sub-pool z

where x = the size of the global pool, and z = the size of the sub-pool.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Tasks

With the addition of the IETF-Standard version of DS-TE, the command has been further extended to
become:
ip rsvp bandwidth x y [ [rdm x {subpool z | bc1 z}] | [mam bc0 x bc1 z]]

where x = the size of the global pool (now called bc0), and z = the size of the sub-pool (now called also
bc1).
Two bandwidth constraint models also have become available, “Russian Dolls” (indicated by the
keyword rdm) and “Maximum Allocation” (mam). The former model allows greater sharing of
bandwidth across all Class Types (bandwidth pools), while the latter protects especially the premium
Class Type. (The IETF Standard makes possible the future implementation of as many as seven
sub-pools within one LSP, instead of just one sub-pool per LSP).

The tunnel mpls traffic-eng bandwidth command

The pre-DS-TE traffic engineering command was
tunnel mpls traffic-eng bandwidth b

where b = the amount of bandwidth this tunnel requires.

So for the original DS-TE, you specified from which pool (global or sub) the tunnel's bandwidth would
come. You could enter
tunnel mpls traffic-eng bandwidth sub-pool b

to indicate that the tunnel should use bandwidth from the sub-pool. Alternatively, you could enter
tunnel mpls traffic-eng bandwidth b

to indicate that the tunnel should use bandwidth from the global pool (which was the default).

With the addition of the IETF-Standard version of DS-TE, the command has been extended to become:
tunnel mpls traffic-eng bandwidth [sub-pool|class-type 1] b

where both sub-pool and class-type 1 indicate the same, smaller bandwidth pool (now called class-type
1). The two keywords can be used interchangeably.

The mpls traffic-eng ds-te commands

The IETF Standard introduces two new commands, one to indicate the Bandwidth Constraints model
mpls traffic-eng ds-te bc-model [rdm | mam]

and one to select the DS-TE mode:

mpls traffic-eng ds-te mode [migration|ietf]

(The concepts of bc-model and DS-TE mode were explained on page 3).

The first command allows you to select between the Russian Dolls Model (rdm) and the Maximum
Allocation Model (mam) of bandwidth constraints.
The second command allows you to transition a network from traditional DS-TE tunnels to the IETF
Standard without disrupting any of the tunnels’ operation. To accomplish this, you first put the routers
into Migration mode (using the migration keyword) and subsequently into the Liberal-IETF mode
(using the ietf keyword).

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Tasks

Transitioning a Network to the IETF Standard

Networks already operating DS-TE tunnels by means of the traditional, pre-IETF-Standard software can
switch to the IETF-Standard without interrupting their DS-TE service by following this sequence:
1. Install Cisco IOS Release 12.2(33)SRB (or a subsequent release) on each router in the network,
gradually, one router at a time, using Cisco’s In Service Software Upgrade (ISSU) procedure which
protects ongoing network traffic from interruption. (After that installation, DS-TE tunnels in the
network will continue to operate by using the pre-IETF-Standard formats.)
2. Enter the global configuration command mpls traffic-eng ds-te mode migration on each router in
the network, one router at a time. This will enable the routers to receive IETF-format IGP
advertisement and RSVP-TE signaling, while the routers will continue to generate and receive the
pre-Standard formats for those two functions.
3. After all the routers in the network have begun to operate in Migration mode, enter the global
configuration command mpls traffic-eng ds-te mode ietf on each router, one at a time. This will
cause the router to refresh its TE tunnels with IETF-compliant Path signaling, without disrupting the
tunnels’ operation. This mode also causes the router to generate IGP advertisement in the
IETF-Standard format.

Configuring DS-TE Tunnels

To establish a sub-pool (BC1) traffic engineering tunnel, you must enter configurations at three levels:
• the device level (router or switch router)
• the physical interface
• the tunnel interface
On the first two levels, you activate traffic engineering; on the third level—the tunnel interface—you
establish the sub-pool tunnel. Therefore, it is only at the tunnel headend device that you need to
configure all three levels. At the tunnel midpoints and tail, it is sufficient to configure the first two levels.
In the tables below, each command is explained in brief. For a more complete explanation of any
command, type it into the Command Lookup Tool at
http://www.cisco.com/cgi-bin/Support/Cmdlookup/home.pl. (If prompted to log in there, use your
Cisco.com account username and password).

Level 1: Configuring the Device

At this level, you tell the device (router or switch router) to use accelerated packet-forwarding (known
as Cisco Express Forwarding or CEF), MultiProtocol Label Switching (MPLS), traffic-engineering
tunneling, a bandwidth constraints model, and either the OSPF or IS-IS routing algorithm (Open

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Tasks

Shortest Path First or Intermediate System to Intermediate System). This level is called the global
configuration mode, because the configuration is applied globally, to the entire device, rather than to a
specific interface or routing instance.
You enter the following commands:

Command Purpose
Step 1 Router(config)# ip cef distributed Enables CEF—which accelerates the flow of packets through the
device.
Step 2 Router(config)# mpls traffic-eng tunnels Enables MPLS, and specifically its traffic engineering tunnel
capability.
Step 3 Router(config)# mpls traffic-eng ds-te Specifies the bandwidth constraints model (see page 3).
bc-model [rdm | mam ]
Step 4 Router(config)# router ospf Invokes the OSPF routing process for IP and puts the device into
router configuration mode. Proceed now to Steps 10 and 11.
[or]
Router(config)# router isis Alternatively, you may invoke the IS-IS routing process with this
command, and continue with Step 5.
Step 5 Router (config-router)# net Specifies the IS-IS network entity title (NET) for the routing
network-entity-title process.
Step 6 Router (config-router)# metric-style wide Enables the router to generate and accept IS-IS new-style TLVs
(type, length, and value objects).
Step 7 Router (config-router)# is-type level-n Configures the router to learn about destinations inside its own
area or “IS-IS level”.
Step 8 Router (config-router)# mpls traffic-eng Specifies the IS-IS level (which must be same level as in the
level-n preceding step) to which the router will flood MPLS traffic-
engineering link information.
Step 9 Router (config-router)# passive-interface Instructs IS-IS to advertise the IP address of the loopback
loopback0 interface without actually running IS-IS on that interface.
Continue with Step 10 but don’t do Step 11—because Step 11
refers to OSPF.
Step 10 Router(config-router)# mpls traffic-eng Specifies that the traffic engineering router identifier is the IP
router-id loopback0 address associated with the loopback0 interface.
Step 11 Router(config-router)# mpls traffic-eng Turns on MPLS traffic engineering for a particular OSPF area.
area num

Level 2: Configuring the Physical Interface

Having configured the device, you now must configure the interface on that device through which the
tunnel will run. To do that, you first put the router into interface-configuration mode.
You then enable Resource Reservation Protocol (RSVP). This protocol is used to signal (set up) a traffic
engineering tunnel, and to tell devices along the tunnel path to reserve a specific amount of bandwidth
for the traffic that will flow through that tunnel. It is with this command that you establish the maximum
size of the sub-pool (BC1).
Finally, you enable the MPLS traffic engineering tunnel feature on this physical interface—and if you
will be relying on the IS-IS routing protocol, you enable that as well.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Tasks

To accomplish these tasks, you enter the following commands:

Command Purpose
Step 1 Router(config)# interface interface-id Moves configuration to the interface level, directing subsequent
configuration commands to the specific interface identified by
the interface-id.
Step 2 Router(config-if)# ip rsvp bandwidth Enables RSVP on this interface, indicates the Bandwidth
[interface-kbps] [single-flow-kbps][[rdm Constraints Model to be used (explained on page 3), and limits
kbps{[subpool kbps]|[bc1 subpool]}]|[mam
max-reservable-bw kbps bc0 kbps bc1 kbps]]
the amount of bandwidth RSVP can reserve on this interface.
The sum of bandwidth used by all tunnels on this interface
cannot exceed interface-kbps. (For more detail, see page 40).
Step 3 Router(config-if)# mpls traffic-eng tunnels Enables the MPLS traffic engineering tunnel feature on this
interface.
Step 4 Router(config-if)# ip router isis Enables the IS-IS routing protocol on this interface. Do not
enter this command if you are configuring for OSPF.

Level 3: Configuring the Tunnel Interface

Now you create a set of attributes for the tunnel itself; those attributes are configured on the “tunnel
interface” (not to be confused with the physical interface just configured above).
You enter the following commands:

Command Purpose
Step 1 Router(config)# interface tunnel1 Creates a tunnel interface (named in this example tunnel1)
and enters interface configuration mode.
Step 2 Router(config-if)# tunnel destination A.B.C.D Specifies the IP address of the tunnel tail device.
Step 3 Router(config-if)# tunnel mode mpls traffic-eng Sets the tunnel’s encapsulation mode to MPLS traffic
engineering.
Step 4 Router(config-if)# tunnel mpls traffic-eng Configures the tunnel’s bandwidth, and assigns it either to
bandwidth {sub-pool|class-type1} bandwidth the sub-pool (when you use that keyword or the
IETF-Standard keyword class-type1) or to the global pool
(when you leave out both keywords). For more detail, see
page 48.
Step 5 Router(config-if)# tunnel mpls traffic-eng Sets the priority to be used when the system determines
priority which existing tunnels are eligible to be preempted.
Step 6 Router(config-if)# tunnel mpls traffic-eng Configures the paths (hops) a tunnel should use. The user
path-option can enter an explicit path (can specify the IP addresses of
the hops) or can specify a dynamic path (the router figures
out the best set of hops).

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Tasks

Verifying the Configuration

To view the complete configuration you have entered, use the EXEC command show running-config
and check its output display for correctness.
To check just one tunnel’s configuration, enter show interfaces tunnel followed by the tunnel interface
number. And to see that tunnel’s RSVP bandwidth and flow, enter show ip rsvp interface followed by
the name or number of the physical interface.
Here is an example of the information displayed by these latter two commands. (To see an explanation
of each field used in the following displays, enter show interfaces tunnel or show ip rsvp interface into
the Command Lookup Tool at http://www.cisco.com/cgi-bin/Support/Cmdlookup/home.pl. If prompted
to log in there, use your Cisco.com account username and password.)
Router#show interfaces tunnel 4
Tunnel4 is up, line protocol is down
Hardware is Routing Tunnel
MTU 1500 bytes, BW 9 Kbit, DLY 500000 usec, rely 255/255, load 1/255
Encapsulation TUNNEL, loopback not set, keepalive set (10 sec)
Tunnel source 0.0.0.0, destination 0.0.0.0
Tunnel protocol/transport GRE/IP, key disabled, sequencing disabled
Last input never, output never, output hang never
Last clearing of “show interface” counters never
Output queue 0/0, 0 drops; input queue 0/75, 0 drops
Five minute input rate 0 bits/sec, 0 packets/sec
Five minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets, 0 restarts

Router#show ip rsvp interface pos4/0

interface allocated i/f max flow max sub max
PO4/0 300K 466500K 466500K 0M

To view all tunnels at once on the router you have configured, enter show mpls traffic-eng tunnels
brief. The information displayed when tunnels are functioning properly looks like this:
Router#show mpls traffic-eng tunnels brief
Signalling Summary:
LSP Tunnels Process: running
RSVP Process: running
Forwarding: enabled
Periodic reoptimization: every 3600 seconds, next in 3029 seconds
TUNNEL NAME DESTINATION UP IF DOWN IF STATE/PROT
GSR1_t0 192.168.1.13 - SR3/0 up/up
GSR1_t1 192.168.1.13 - SR3/0 up/up
GSR1_t2 192.168.1.13 - PO4/0 up/up
Displayed 3 (of 3) heads, 0 (of 0) midpoints, 0 (of 0) tails

When one or more tunnels is not functioning properly, the display could instead look like this. (In the
following example, tunnels t0 and t1 are down, as indicated in the far right column).
Router#show mpls traffic-eng tunnels brief
Signalling Summary:
LSP Tunnels Process: running
RSVP Process: running
Forwarding: enabled
Periodic reoptimization: every 3600 seconds, next in 2279 seconds
TUNNEL NAME DESTINATION UP IF DOWN IF STATE/PROT
GSR1_t0 192.168.1.13 - SR3/0 up/down

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Configuration Tasks

GSR1_t1 192.168.1.13 - SR3/0 up/down

GSR1_t2 192.168.1.13 - PO4/0 up/up
Displayed 3 (of 3) heads, 0 (of 0) midpoints, 0 (of 0) tails

To find out why a tunnel is down, insert its name into this same command, after adding the keyword
name and omitting the keyword brief. For example:
Router#show mpls traffic-eng tunnels name GSR1_t0
Name:GSR1_t0 (Tunnel0) Destination:192.168.1.13
Status:
Admin:up Oper:down Path: not valid Signalling:connected

If, as in this example, the Path is displayed as not valid, use the show mpls traffic-eng topology
command to make sure the router has received the needed updates.

Additionally, you can use any of the following show commands to inspect particular aspects of the
network, router, or interface concerned:

To see information about...

this level and this item... Use this command
Network Advertised bandwidth show mpls traffic-eng link-management advertisements
allocation information
Preemptions along the debug mpls traffic-eng link-management preemption
tunnel path
Available TE link band- show mpls traffic-eng topology (described on page 49)
width on all head routers
Router Status of all tunnels cur- show mpls traffic-eng link-management
rently signalled by this admission-control
router
Tunnels configured on show mpls traffic-eng link-management summary
midpoint routers
Physical Detailed information on show mpls traffic-eng link-management
interface current bandwidth pools bandwidth-allocation [interface-name]
TE RSVP bookkeeping show mpls traffic-eng link-management interfaces
Entire configuration of show run interface
one interface

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Configuration Examples

Configuration Examples
Note The following 25 pages of examples illustrate DS-TE in the traditional, pre-IETF-Standard mode. You
may update these examples simply by inserting the new Device Level command mpls traffic-eng ds-te
bc-model as its proper use is shown in Step 3 on page 9, and by applying the updated syntax within the
two modified commands as each is shown respectively at the Physical Interface Level in Step 2 on page
10 (ip rsvp bandwidth), and at the Tunnel Interface Level in Step 4 on page 10 (tunnel mpls traffic-eng
bandwidth).

First this section presents the DS-TE configurations needed to create the sub-pool tunnel. Then it
presents the more comprehensive design for building end-to-end guaranteed bandwidth service, which
involves configuring Quality of Service as well.
As shown in Figure 1, the tunnel configuration involves at least three devices—tunnel head, midpoint,
and tail. On each of those devices one or two network interfaces must be configured, for traffic ingress
and egress.

Figure 1 Sample Tunnel Topology

Lo0: 22.1.1.1 Lo0: 25.1.1.1 Lo0: 24.1.1.1

Head Mid Tail
(router-1) (router-2) (router-3)

10.1.1.0 12.1.1.0
POS2/0/0 POS4/0 POS4/1 POS2/0

= Data flow

53559
= Sub-pool tunnel

Tunnel Head
At the device level:
router-1# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.

router-1(config)# ip cef distributed

router-1(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-1(config)# router isis router ospf 100
router-1(config-router)# net redistribute connected
49.0000.1000.0000.0010.00
router-1(config-router)# metric-style wide network 10.1.1.0 0.0.0.255 area 0
router-1(config-router)# is-type level-1 network 22.1.1.1 0.0.0.0 area 0

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Configuration Examples

router-1(config-router)# mpls traffic-eng mpls traffic-eng area 0

level-1
router-1(config-router)# passive-interface
Loopback0
[now one resumes the common command set]:
router-1(config-router)# mpls traffic-eng router-id Loopback0
router-1(config-router)# exit

router-1(config)# interface Loopback0

At the virtual interface level:

router-1(config-if)# ip address 22.1.1.1 255.255.255.255
router-1(config-if)# no ip directed-broadcast
router-1(config-if)# exit

At the device level:

router-1(config)# interface POS2/0/0

At the physical interface level (egress):

router-1(config-if)# ip address 10.1.1.1 255.255.255.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 130000 130000 sub-pool 80000
[and if using IS-IS instead of OSPF]:
router-1(config-if)# ip router isis
[and in all cases]:
router-1(config-if)# exit

At the device level:

router-1(config)# interface Tunnel1

At the tunnel interface level:

router-1(config-if)# bandwidth 110000
router-1(config-if)# ip unnumbered Loopback0
router-1(config-if)# tunnel destination 24.1.1.1
router-1(config-if)# tunnel mode mpls traffic-eng
router-1(config-if)# tunnel mpls traffic-eng priority 0 0
router-1(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 30000
router-1(config-if)# tunnel mpls traffic-eng path-option 1 dynamic
router-1(config-if)# exit
router-1(config)#

Midpoint Devices
At the device level:
router-2# configure terminal
router-2(config)# ip cef distributed
router-2(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-2(config)# router isis router ospf 100
router-2(config-router)# net redistribute connected
49.0000.1000.0000.0012.00

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router-2(config-router)# metric-style wide network 11.1.1.0 0.0.0.255 area 0

router-2(config-router)# is-type level-1 network 12.1.1.0 0.0.0.255 area 0
router-2(config-router)# mpls traffic-eng network 25.1.1.1 0.0.0.0 area 0
level-1
router-2(config-router)# passive-interface mpls traffic-eng area 0
Loopback0
[now one resumes the common command set]:
router-2(config-router)# mpls traffic-eng router-id Loopback0
router-2(config-router)# exit

router-2(config)# interface Loopback0

At the virtual interface level:

router-2(config-if)# ip address 25.1.1.1 255.255.255.255
router-2(config-if)# no ip directed-broadcast
router-2(config-if)# exit

At the device level:

router-1(config)# interface POS4/0
router-1(config-if)# ip address 11.1.1.2 255.255.255.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 130000 130000 sub-pool 80000

[If using IS-IS instead of OSPF]:

router-1(config-if)# ip router isis
[and in all cases]:
router-1(config-if)# exit

At the device level:

router-1(config)# interface POS4/1
router-1(config-if)# ip address 12.1.1.2 255.255.255.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 130000 130000 sub-pool 80000

[If using IS-IS instead of OSPF]:

router-1(config-if)# ip router isis
[and in all cases]:
router-1(config-if)# exit

Note that there is no configuring of tunnel interfaces at the mid-point devices, only network interfaces
and the device globally.

Tail-End Device
At the device level:
router-3# configure terminal
router-3(config)# ip cef distributed
router-3(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-3(config)# router isis router ospf 100
router-3(config-router)# net redistribute connected
49.0000.1000.0000.0013.00
router-3(config-router)# metric-style wide network 12.1.1.0 0.0.0.255 area 0
router-3(config-router)# is-type level-1 network 24.1.1.1 0.0.0.0 area 0

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Configuration Examples

router-3(config-router)# mpls traffic-eng level-1 mpls traffic-eng area 0

router-3(config-router)# passive-interface
Loopback0
[now one resumes the common command set]:
router-3(config-router)# mpls traffic-eng router-id Loopback0
router-3(config-router)# exit

router-3(config)# interface Loopback0

At the virtual interface level:

router-3(config-if)# ip address 24.1.1.1 255.255.255.255
router-3(config-if)# no ip directed-broadcast
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

At the device level:

router-1(config)# interface POS4/0
router-1(config-if)# ip address 12.1.1.3 255.255.255.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 130000 130000 sub-pool 80000

[If using IS-IS instead of OSPF]:

router-1(config-if)# ip router isis
[and in all cases]:
router-1(config-if)# exit

Guaranteed Bandwidth Service Configuration

Having configured two bandwidth pools, you now can
• Use one pool, the sub-pool, for tunnels that carry traffic requiring strict bandwidth guarantees or
delay guarantees
• Use the other pool, the global pool, for tunnels that carry traffic requiring only Differentiated
Service.
Having a separate pool for traffic requiring strict guarantees allows you to limit the amount of such
traffic admitted on any given link. Often, it is possible to achieve strict QoS guarantees only if the
amount of guaranteed traffic is limited to a portion of the total link bandwidth.
Having a separate pool for other traffic (best-effort or diffserv traffic) allows you to have a separate limit
for the amount of such traffic admitted on any given link. This is useful because it allows you to fill up
links with best-effort/diffserv traffic, thereby achieving a greater utilization of those links.

Providing Strict QoS Guarantees Using DS-TE Sub-pool Tunnels

A tunnel using sub-pool bandwidth can satisfy the stricter requirements if you do all of the following:
1. Select a queue—or in diffserv terminology, select a PHB (per-hop behavior)—to be used exclusively
by the strict guarantee traffic. This shall be called the “GB queue.”
If delay/jitter guarantees are sought, the diffserv Expedited Forwarding queue (EF PHB) is used. On
the Cisco 7500(VIP) it is the "priority" queue.You must configure the bandwidth of the queue to be
at least equal to the bandwidth of the sub-pool.

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Configuration Examples

If only bandwidth guarantees are sought, the diffserv Assured Forwarding PHB (AF PHB) is used.
On the Cisco 7500 (VIP) you use one of the existing Class-Based Weighted Fair Queuing (CBWFQ)
queues.
2. Ensure that the guaranteed traffic sent through the sub-pool tunnel is placed in the GB queue at the
outbound interface of every tunnel hop, and that no other traffic is placed in this queue.
You do this by marking the traffic that enters the tunnel with a unique value in the mpls exp bits
field, and steering only traffic with that marking into the GB queue.
3. Ensure that this GB queue is never oversubscribed; that is, see that no more traffic is sent into the
sub-pool tunnel than the GB queue can handle.
You do this by rate-limiting the guaranteed traffic before it enters the sub-pool tunnel. The aggregate
rate of all traffic entering the sub-pool tunnel should be less than or equal to the bandwidth capacity
of the sub-pool tunnel. Excess traffic can be dropped (in the case of delay/jitter guarantees) or can
be marked differently for preferential discard (in the case of bandwidth guarantees).
4. Ensure that the amount of traffic entering the GB queue is limited to an appropriate percentage of
the total bandwidth of the corresponding outbound link. The exact percentage to use depends on
several factors that can contribute to accumulated delay in your network: your QoS performance
objective, the total number of tunnel hops, the amount of link fan-in along the tunnel path, burstiness
of the input traffic, and so on.
You do this by setting the sub-pool bandwidth of each outbound link to the appropriate percentage
of the total link bandwidth (that is, by adjusting the z parameter of the ip rsvp bandwidth
command).

Providing Differentiated Service Using DS-TE Global Pool Tunnels

You can configure a tunnel using global pool bandwidth to carry best-effort as well as several other
classes of traffic. Traffic from each class can receive differentiated service if you do all of the following:
1. Select a separate queue (a distinct diffserv PHB) for each traffic class. For example, if there are three
classes (gold, silver, and bronze) there must be three queues (diffserv AF2, AF3, and AF4).
2. Mark each class of traffic using a unique value in the MPLS experimental bits field (for example
gold = 4, silver = 5, bronze = 6).
3. Ensure that packets marked as Gold are placed in the gold queue, Silver in the silver queue, and so
on. The tunnel bandwidth is set based on the expected aggregate traffic across all classes of service.
To control the amount of diffserv tunnel traffic you intend to support on a given link, adjust the size of
the global pool on that link.

Providing Strict Guarantees and Differentiated Service in the Same Network

Because DS-TE allows simultaneous constraint-based routing of sub-pool and global pool tunnels, strict
guarantees and diffserv can be supported simultaneously in a given network.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

Guaranteed Bandwidth Service Examples

Given the many topologies in which Guaranteed Bandwidth Services can be applied, there is space here
only to present two examples. They illustrate opposite ends of the spectrum of possibilities.
In the first example, the guaranteed bandwidth tunnel can be easily specified by its destination. So the
forwarding criteria refer to a single destination prefix.
In the second example, there can be many final destinations for the guaranteed bandwidth traffic,
including a dynamically changing number of destination prefixes. So the forwarding criteria are
specified by Border Gateway Protocol (BGP) policies.

Example with Single Destination Prefix

Figure 2 illustrates a topology for guaranteed bandwidth services whose destination is specified by a
single prefix, either Site D (like a voice gateway, here bearing prefix 26.1.1.1) or a subnet (like the
location of a web farm, here called “Province” and bearing prefix 26.1.1.0). Three services are offered:
• From Site A (defined as all traffic arriving at interface FE4/1/0): to host 26.1.1.1, 8 Mbps of
guaranteed bandwidth with low loss, low delay and low jitter
• From Site B (defined as all traffic arriving at interface FE4/1/1): towards subnet 26.1.1.0, 32 Mbps
of guaranteed bandwidth with low loss
• From Site C (defined as all traffic arriving at interface FE2/1/0): 30 Mbps of guaranteed bandwidth
with low loss

Figure 2 Sample Topology for Guaranteed Bandwidth Services to a Single Destination Prefix

23.1.1.1
Head-1

140/60
8 40
FE4/1/0 POS4/0

FE4/1/1
Site A
32 26.1.1.1
Mid-1 Tail

26.1.1.0
140/60 Province
Site B 40
POS2/1 POS3/1 POS2/1 Site D
POS
POS1/1 POS4/1 2/2
22.1.1.1
Head-2 30 140/60 30 140/60

Mid-2
140/60
30 30
FE2/1/0 POS0/0

Site C POS1/1 POS2/1

8
= Data flow (service bandwidth indicated in Mbps [megabits per second])
49947

140/60
= Sub-pool tunnel (global and sub-pool bandwidth indicated in Mbps for this link)

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

These three services run through two sub-pool tunnels:

• From the Head-1 router, 23.1.1.1, to the router-4 tail
• From the Head-2 router, 22.1.1.1, to the router-4 tail
Both tunnels use the same tail router, though they have different heads. (In Figure 2 one midpoint router
is shared by both tunnels. In the real world there could of course be many more midpoints.)
All POS interfaces in this example are OC3, whose capacity is 155 Mbps.

Configuring Tunnel Head-1

First we recapitulate commands that establish two bandwidth pools and a sub-pool tunnel (as presented
earlier in this Configuration Examples section). Then we present the QoS commands that guarantee
end-to-end service on the subpool tunnel. (With the 7500 router, Modular QoS CLI is used.)

Configuring the Pools and Tunnel

At the device level:

router-1(config)# ip cef distributed
router-1(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router ospf 100
router-1(config)# router isis
router-1(config-router)# net redistribute connected
49.0000.1000.0000.0010.00
router-1(config-router)# metric-style wide network 10.1.1.0 0.0.0.255 area 0
router-1(config-router)# is-type level-1 network 23.1.1.1 0.0.0.0 area 0
router-1(config-router)# mpls traffic-eng mpls traffic-eng area 0
level-1
router-1(config-router)# passive-interface
Loopback0
[now one resumes the common command set]:
router-1(config-router)# mpls traffic-eng router-id Loopback0
router-1(config-router)# exit

Create a virtual interface:

router-1(config)# interface Loopback0
router-1(config-if)# ip address 23.1.1.1 255.255.255.255
router-1(config-if)# no ip directed-broadcast
router-1(config-if)# exit

At the outgoing physical interface:

router-1(config)# interface pos4/0
router-1(config-if)# ip address 10.1.1.1 255.0.0.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-1(config-if)# ip router isis
[and in all cases}:
router-1(config-if)# exit

At the tunnel interface:

router-1(config)# interface Tunnel1
router-1(config-if)# bandwidth 110000
router-1(config-if)# ip unnumbered Loopback0
router-1(config-if)# tunnel destination 27.1.1.1

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

router-1(config-if)# tunnel mode mpls traffic-eng

router-1(config-if)# tunnel mpls traffic-eng priority 0 0
router-1(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 40000
router-1(config-if)# tunnel mpls traffic-eng path-option 1 dynamic

To ensure that packets destined to host 26.1.1.1 and subnet 26.1.1.0 are sent into the sub-pool tunnel, we
create a static route. At the device level:
router-1(config)# ip route 26.1.1.0 255.255.255.0 Tunnel1
router-1(config)# exit

And in order to make sure that the Interior Gateway Protocol (IGP) will not send any other traffic down
this tunnel, we disable autoroute announce:
router-1(config)# no tunnel mpls traffic-eng autoroute announce

For Service from Site A to Site D

At the inbound physical interface (FE4/1/0):

1. In global configuration mode, create a class of traffic matching ACL 100, called "sla-1-class":
class-map match-all sla-1-class
match access-group 100

2. Create an ACL 100 to refer to all packets destined to 26.1.1.1:

access-list 100 permit ip any host 26.1.1.1

3. Create a policy named “sla-1-input-policy”, and according to that policy:

a. Packets in the class called “sla-1-class” are rate-limited to:
– a rate of 8 million bits per second
– a normal burst of 1 million bytes
– a maximum burst of 2 million bytes
b. Packets which conform to this rate are marked with MPLS experimental bit 5 and are forwarded.
c. Packets which exceed this rate are dropped.
d. All other packets are marked with experimental bit 0 and are forwarded.
policy-map sla-1-input-policy
class sla-1-class
police 8000000 1000000 2000000 conform-action set-mpls-exp-transmit 5 \
exceed-action drop
class class-default
set-mpls-exp-transmit 0

4. The policy is applied to packets entering interface FE4/1/0.

interface FastEthernet4/1/0
service-policy input sla-1-input-policy

For Service from Site B to Subnet “Province”

At the inbound physical interface (FE4/1/1):

1. In global configuration mode, create a class of traffic matching ACL 120, called "sla-2-class":
class-map match-all sla-2-class
match access-group 120

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

2. Create an ACL, 120, to refer to all packets destined to subnet 26.1.1.0:

access-list 120 permit ip any 26.1.1.0 0.0.0.255

3. Create a policy named “sla-2-input-policy”, and according to that policy:

a. Packets in the class called “sla-2-class” are rate-limited to:
– a rate of 32 million bits per second
– a normal burst of 1 million bytes
– a maximum burst of 2 million bytes
b. Packets which conform to this rate are marked with MPLS experimental bit 5 and are forwarded.
c. Packets which exceed this rate are dropped.
d. All other packets are marked with experimental bit 0 and are forwarded.
policy-map sla-2-input-policy
class sla-2-class
police 32000000 1000000 2000000 conform-action set-mpls-exp-transmit 5 \
exceed-action drop
class class-default
set-mpls-exp-transmit 0

4. The policy is applied to packets entering interface FE4/1/1.

interface FastEthernet4/1/1
service-policy input sla-2-input-policy

For Both Services

The outbound interface (POS4/0) is configured as follows:

1. In global configuration mode, create a class of traffic matching experimental bit 5, called
"exp-5-traffic".
class-map match-all exp-5-traffic
match mpls experimental 5

2. Create a policy named “output-interface-policy”. According to that policy, packets in the class
“exp-5-traffic” are put in the priority queue (which is rate-limited to 62 kbits/sec).
policy-map output-interface-policy
class exp-5-traffic
priority 32

3. The policy is applied to packets exiting interface POS4/0.

interface POS4/0
service-policy output output-interface-policy

The result of the above configuration lines is that packets entering the Head-1 router via interface
FE4/1/0 destined to host 26.1.1.1, or entering the router via interface FE4/1/1 destined to subnet
26.1.1.0, will have their MPLS experimental bit set to 5. We assume that no other packets entering the
router (on any interface) are using this value. (If this cannot be assumed, an additional configuration
must be added to mark all such packets to another experimental value.) Packets marked with
experimental bit 5, when exiting the router via interface POS4/0, will be placed into the priority queue.

Note Packets entering the router via FE4/1/0 or FE4/1/1 and exiting POS4/0 enter as IP packets and exit
as MPLS packets.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

Configuring Tunnel Head-2

First we recapitulate commands that establish two bandwidth pools and a sub-pool tunnel (as presented
earlier in this Configuration Examples section). Then we present the QoS commands that guarantee
end-to-end service on the sub-pool tunnel.

.Configuring the Pools and Tunnel

At the device level:

router-2(config)# ip cef distributed
router-2(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-2(config)# router isis router ospf 100
router-2(config-router)# net redistribute connected
49.0000.1000.0000.0011.00
router-2(config-router)# metric-style wide network 11.1.1.0 0.0.0.255 area 0
router-2(config-router)# is-type level-1 network 22.1.1.1 0.0.0.0 area 0
router-2(config-router)# mpls traffic-eng mpls traffic-eng area 0
level-1
router-2(config-router)# passive-interface
Loopback0
[now one resumes the common command set]:
router-2(config-router)# mpls traffic-eng router-id Loopback0
router-2(config-router)# exit

Create a virtual interface:

router-2(config)# interface Loopback0
router-2(config-if)# ip address 22.1.1.1 255.255.255.255
router-2(config-if)# no ip directed broadcast
router-2(config-if)# exit

At the outgoing physical interface:

router-2(config)# interface pos0/0
router-2(config-if)# ip address 11.1.1.1 255.0.0.0
router-2(config-if)# mpls traffic-eng tunnels
router-2(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-2(config-if)# ip router isis
[and in all cases]:
router-2(config-if)# exit

At the tunnel interface:

router-2(config)# interface Tunnel2
router-2(config-if)# ip unnumbered Loopback0
router-2(config-if)# tunnel destination 27.1.1.1
router-2(config-if)# tunnel mode mpls traffic-eng
router-2(config-if)# tunnel mpls traffic-eng priority 0 0
router-2(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 30000
router-2(config-if)# tunnel mpls traffic-eng path-option 1 dynamic
router-2(config-if)# exit

And to ensure that packets destined to subnet 26.1.1.0 are sent into the sub-pool tunnel, we create a static
route, at the device level:
router-2(config)# ip route 26.1.1.0 255.255.255.0 Tunnel2
router-2(config)# exit

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

Finally, in order to make sure that the Interior Gateway Protocol (IGP) will not send any other traffic
down this tunnel, we disable autoroute announce:
router-2(config)# no tunnel mpls traffic-eng autoroute announce

For Service from Site C to Subnet “Province”

At the inbound physical interface (FE2/1/0):

1. In global configuration mode, create a class of traffic matching ACL 130, called "sla-3-class":
class-map match-all sla-3-class
match access-group 130

2. Create an ACL, 130, to refer to all packets destined to subnet 26.1.1.0:

access-list 130 permit ip any 26.1.1.0 0.0.0.255

3. Create a policy named “sla-3-input-policy”, and according to that policy:

a. Packets in the class called “sla-3-class” are rate-limited to:
– a rate of 30 million bits per second
– a normal burst of 1 million bytes
– a maximum burst of 2 million bytes
b. Packets which conform to this rate are marked with MPLS experimental bit 5 and are forwarded.
c. Packets which exceed this rate are dropped.
d. All other packets are marked with experimental bit 0 and are forwarded.
policy-map sla-3-input-policy
class sla-3-class
police 30000000 1000000 2000000 conform-action set-mpls-exp-transmit 5 \
exceed-action drop
class class-default
set-mpls-exp-transmit 0

4. The policy is applied to packets entering interface FE2/1/0.

interface FastEthernet2/1/0
service-policy input sla-3-input-policy

The outbound interface POS0/0 is configured as follows:

1. In global configuration mode, create a class of traffic matching experimental bit 5, called
"exp-5-traffic".
class-map match-all exp-5-traffic
match mpls experimental 5

2. Create a policy named “output-interface-policy”. According to that policy, packets in the class
“exp-5-traffic” are put in the priority queue (which is rate-limited to 32 kbits/sec).
policy-map output-interface-policy
class exp-5-traffic
priority 32

3. The policy is applied to packets exiting interface POS0/0:

interface POS0/0
service-policy output output-interface-policy

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

As a result of all the above configuration lines, packets entering the Head-2 router via interface FE2/1/0
and destined for subnet 26.1.1.0 have their IP precedence field set to 5. It is assumed that no other
packets entering this router (on any interface) are using this precedence. (If this cannot be assumed, an
additional configuration must be added to mark all such packets with another precedence value.) When
exiting this router via interface POS0/0, packets marked with precedence 5 are placed in the priority
queue.

Note Packets entering the router via FE2/1/0 and exiting through POS0/0 enter as IP packets and exit
as MPLS packets.

Tunnel Midpoint Configuration [Mid-1]

All four interfaces on the midpoint router are configured identically to the outbound interface of the head
router (except, of course, for the IDs of the individual interfaces):

Configuring the Pools and Tunnels

At the device level:

router-3(config)# ip cef distributed
router-3(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-3(config)# router isis router ospf 100
router-3(config-router)# net redistribute connected
49.0000.2400.0000.0011.00
router-3(config-router)# metric-style wide network 10.1.1.0 0.0.0.255 area 0
router-3(config-router)# is-type level-1 network 11.1.1.0 0.0.0.255 area 0
router-3(config-router)# mpls traffic-eng level-1 network 24.1.1.1 0.0.0.0 area 0
router-3(config-router)# passive-interface network 12.1.1.0 0.0.0.255 area 0
Loopback0
router-3(config-router)# network 13.1.1.0 0.0.0.255 area 0
router-3(config-router)# mpls traffic-eng area 0
[now one resumes the common command set]:
router-3(config-router)# mpls traffic-eng router-id Loopback0
router-3(config-router)# exit

Create a virtual interface:

router-3(config)# interface Loopback0
router-3(config-if)# ip address 24.1.1.1 255.255.255.255
router-3(config-if)# exit

At the physical interface level (ingress):

router-3(config)# interface pos2/1
router-3(config-if)# ip address 10.1.1.2 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

router-3(config)# interface pos1/1

router-3(config-if)# ip address 11.1.1.2 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000

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[and if using IS-IS instead of OSPF]:

router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

At the physical interface level (egress):

router-3(config)# interface pos3/1
router-3(config-if)# ip address 12.1.1.1 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

router-3(config)# interface pos4/1

router-3(config-if)# ip address 13.1.1.1 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

Tunnel Midpoint Configuration [Mid-2]

Both interfaces on the midpoint router are configured identically to the outbound interface of the head
router (except, of course, for the IDs of the individual interfaces):

Configuring the Pools and Tunnel

At the device level:

router-5(config)# ip cef distributed
router-5(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-5(config)# router isis router ospf 100
router-5(config-router)# net redistribute connected
49.2500.1000.0000.0012.00
router-5(config-router)# metric-style wide network 13.1.1.0 0.0.0.255 area 0
router-5(config-router)# is-type level-1 network 14.1.1.0 0.0.0.255 area 0
router-5(config-router)# mpls traffic-eng network 25.1.1.1 0.0.0.0 area 0
level-1
router-5(config-router)# passive-interface mpls traffic-eng area 0
Loopback0
[now one resumes the common command set]:
router-5(config-router)# mpls traffic-eng router-id Loopback0
router-5(config-router)# exit

Create a virtual interface:

router-5(config)# interface Loopback0
router-5(config-if)# ip address 25.1.1.1 255.255.255.255
router-5(config-if)# exit

At the physical interface level (ingress):

router-5(config)# interface pos1/1

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router-5(config-if)# ip address 13.1.1.2 255.0.0.0

router-5(config-if)# mpls traffic-eng tunnels
router-5(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-5(config-if)# ip router isis
[and in all cases]:
router-5(config-if)# exit

At the physical interface level (egress):

router-5(config)# interface pos2/1
router-5(config-if)# ip address 14.1.1.1 255.0.0.0
router-5(config-if)# mpls traffic-eng tunnels
router-5(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-5(config-if)# ip router isis
[and in all cases]:
router-5(config-if)# exit

Tunnel Tail Configuration

The inbound interfaces on the tail router are configured identically to the inbound interfaces of the
midpoint routers (except, of course, for the ID of each particular interface):

Configuring the Pools and Tunnels

At the device level:

router-4(config)# ip cef distributed
router-4(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-4(config)# router isis router ospf 100
router-4(config-router)# net redistribute connected
49.0000.2700.0000.0000.00
router-4(config-router)# metric-style wide network 12.1.1.0 0.0.0.255 area 0
router-4(config-router)# is-type level-1 network 14.1.1.0 0.0.0.255 area 0
router-4(config-router)# mpls traffic-eng network 27.1.1.1 0.0.0.0 area 0
level-1
router-4(config-router)# passive-interface mpls traffic-eng area 0
Loopback0
[now one resumes the common command set]:
router-4(config-router)# mpls traffic-eng router-id Loopback0
router-4(config-router)# exit

Create a virtual interface:

router-4(config)# interface Loopback0
router-4(config-if)# ip address 27.1.1.1 255.255.255.255
router-4(config-if)# exit

At the physical interface (ingress):

router-4(config)# interface pos2/1
router-4(config-if)# ip address 12.1.1.2 255.0.0.0
router-4(config-if)# mpls traffic-eng tunnels
router-4(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:

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router-4(config-if)# exit

router-4(config)# interface pos2/2

router-4(config-if)# ip address 14.1.1.2 255.0.0.0
router-4(config-if)# mpls traffic-eng tunnels
router-4(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:
router-4(config-if)# exit

Because the tunnel ends on the tail (does not include any outbound interfaces of the tail router), no
outbound QoS configuration is used.

Example with Many Destination Prefixes

Figure 3 illustrates a topology for guaranteed bandwidth services whose destinations are a set of
prefixes. Those prefixes usually share some common properties such as belonging to the same
Autonomous System (AS) or transiting through the same AS. Although the individual prefixes may
change dynamically because of route flaps in the downstream autonomous systems, the properties the
prefixes share will not change. Policies addressing the destination prefix set are enforced through Border
Gateway Protocol (BGP), which is described in the following documents:
• “Configuring QoS Policy Propagation via Border Gateway Protocol” in the Cisco IOS Quality of
Service Solutions Configuration Guide, Release 12.1
(http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/qos_c/qcprt1/qcdprop.htm)
• “Configuring BGP” in the Cisco IOS IP and IP Routing Configuration Guide, Release 12.1
(http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ip_c/ipcprt2/1cdbgp.h
tm)
• “BGP Commands” in the Cisco IOS IP and IP Routing Command Reference, Release 12.1
(http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ip_r/iprprt2/1rdbgp.ht
m)
• “BGP-Policy Command” in the Cisco IOS Quality of Service Solutions Command Reference,
Release 12.1
(http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/qos_r/qrdcmd1.htm
#xtocid89313)
In this example, three guaranteed bandwidth services are offered, each coming through a 7500 or a 12000
edge device:
• Traffic coming from Site A (defined as all traffic arriving at interface FE4/1/0) and from Site C
(defined as all traffic arriving at interface FE2/1) destined to AS5
• Traffic coming from Sites A and C that transits AS5 but is not destined to AS5. (In the figure, the
transiting traffic will go to AS6 and AS7)
• Traffic coming from Sites A and C destined to prefixes advertised with a particular BGP community
attribute (100:1). In this example, Autonomous Systems #3, #5, and #8 are the BGP community
assigned the attribute 100:1.

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Figure 3 Sample Topology for Guaranteed Bandwidth Service to Many Destination Prefixes

AS2
23.1.1.1
Head-1

AS3* AS7

FE4/1/0 POS4/0

Site A 24.1.1.1 27.1.1.1

Mid-1 Tail

AS5* AS6
POS2/1 POS3/1 POS2/1
POS
POS1/1 POS4/1 2/2
22.1.1.1
Head-2
25.1.1.1
Mid-2
AS4 AS8*
FE2/1 POS0/0

Site C POS1/1 POS2/1

*BGP Community 100:1

= Data flow
= Sub-pool tunnel; guaranteed bandwidth service

59025
= Global pool tunnel; best-effort service

The applicability of guaranteed bandwidth service is not limited to the three types of multiple destination
scenarios described above. There is not room in this document to present all possible scenarios. These
three were chosen as representative of the wide range of possible deployments.
The guaranteed bandwidth services run through two sub-pool tunnels:
• From the Head-1 router, 23.1.1.1, to the tail
• From the Head-2 router, 22.1.1.1, to that same tail
In addition, a global pool tunnel has been configured from each head end, to carry best-effort traffic to
the same destinations. All four tunnels use the same tail router, even though they have different heads
and differ in their passage through the midpoints. (Of course in the real world there would be many more
midpoints than just the two shown here.)
All POS interfaces in this example are OC3, whose capacity is 155 Mbps.
Configuring a multi-destination guaranteed bandwidth service involves:
a. Building a sub-pool MPLS-TE tunnel
b. Configuring DiffServ QoS
c. Configuring QoS Policy Propagation via BGP (QPPB)
d. Mapping traffic onto the tunnels
All of these tasks are included in the following example.

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Configuration of Tunnel Head-1

First we recapitulate commands that establish a sub-pool tunnel (commands presented earlier on page
13) and now we also configure a global pool tunnel. Additionally, we present QoS and BGP commands
that guarantee end-to-end service on the sub-pool tunnel. (With the 7500(VIP) router, Modular QoS CLI
is used).

Configuring the Pools and Tunnels

At the device level:

router-1(config)# ip cef distributed
router-1(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router ospf 100
router-1(config)# router isis
router-1(config-router)# net redistribute connected
49.0000.1000.0000.0010.00
router-1(config-router)# metric-style wide network 10.1.1.0 0.0.0.255 area 0
router-1(config-router)# is-type level-1 network 23.1.1.1 0.0.0.0 area 0
router-1(config-router)# mpls traffic-eng mpls traffic-eng area 0
level-1
[now one resumes the common command set]:
router-1(config-router)# mpls traffic-eng router-id Loopback0
router-1(config-router)# exit

Create a virtual interface:

router-1(config)# interface Loopback0
router-1(config-if)# ip address 23.1.1.1 255.255.255.255
router-1(config-if)# exit

At the outgoing physical interface:

router-1(config)# interface pos4/0
router-1(config-if)# ip address 10.1.1.1 255.0.0.0
router-1(config-if)# mpls traffic-eng tunnels
router-1(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-1(config-if)# ip router isis
[and in all cases]:
router-1(config-if)# exit

At one tunnel interface, create a sub-pool tunnel:

router-1(config)# interface Tunnel1
router-1(config-if)# ip unnumbered Loopback0
router-1(config-if)# tunnel destination 27.1.1.1
router-1(config-if)# tunnel mode mpls traffic-eng
router-1(config-if)# tunnel mpls traffic-eng priority 0 0
router-1(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 40000
router-1(config-if)# tunnel mpls traffic-eng path-option 1 explicit name gbs-path1
router-1(config-if)# exit

and at a second tunnel interface, create a global pool tunnel:

router-1(config)# interface Tunnel2
router-1(config-if)# ip unnumbered Loopback0
router-1(config-if)# tunnel destination 27.1.1.1
router-1(config-if)# tunnel mode mpls traffic-eng
router-1(config-if)# tunnel mpls traffic-eng priority 0 0
router-1(config-if)# tunnel mpls traffic-eng bandwidth 80000

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router-1(config-if)# tunnel mpls traffic-eng path-option 1 explicit name \

best-effort-path1
router-1(config-if)# exit

In this example explicit paths are used instead of dynamic, to ensure that best-effort traffic and
guaranteed bandwidth traffic will travel along different paths.
At the device level:
router-1(config)# ip explicit-path name gbs-path1
router-1(config-ip-expl-path)# next-address 24.1.1.1
router-1(config-ip-expl-path)# next-address 27.1.1.1
router-1(config-ip-expl-path)# exit
router-1(config)# ip explicit-path name best-effort-path1
router-1(config-ip-expl-path)# next-address 24.1.1.1
router-1(config-ip-expl-path)# next-address 25.1.1.1
router-1(config-ip-expl-path)# next-address 27.1.1.1
router-1(config-ip-expl-path)# exit

Note that autoroute is not used, as that could cause the Interior Gateway Protocol (IGP) to send other
traffic down these tunnels.

Configuring DiffServ QoS

At the inbound physical interface (in Figure 3 this is FE4/1/0), packets received are rate-limited to:
a. a rate of 30 Mbps
b. a normal burst of 1 MB
c. a maximum burst of 2 MB
Packets that are mapped to qos-group 6 and that conform to the rate-limit are marked with experimental
value 5 and the BGP destination community string, and are forwarded; packets that do not conform
(exceed action) are dropped:
router-1(config)# interface FastEthernet4/1/0
router-1(config-if)# rate-limit input qos-group 6 30000000 1000000 2000000 \
conform-action set-mpls-exp-transmit 5 exceed-action drop
router-1(config-if)# bgp-policy destination ip-qos-map
router-1(config-if)# exit

At the device level create a class of traffic called “exp5-class” that has MPLS experimental bit set to 5:
router-1(config)# class-map match-all exp5-class
router-1(config-cmap)# match mpls experimental 5
router-1(config-cmap)# exit

Create a policy that creates a priority queue for “exp5-class”:

router-1(config)# policy-map core-out-policy
router-1(config-pmap)# class exp5-class
router-1(config-pmap-c)# priority 100000
router-1(config-pmap-c)# exit
router-1(config-pmap)# class class-default
router-1(config-pmap-c)# bandwidth 55000
router-1(config-pmap-c)# exit
router-1(config-pmap)# exit

The policy is applied to packets exiting the outbound interface POS4/0.

router-1(config)# interface POS4/0
router-1(config-if)# service-policy output core-out-policy

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Configuring QoS Policy Propagation via BGP

For All GB Services

Create a table map under BGP to map (tie) the prefixes to a qos-group. At the device level:
router-1(config)# ip bgp-community new-format
router-1(config)# router bgp 2
router-1(config-router)# no synchronization
router-1(config-router)# table-map set-qos-group
router-1(config-router)# bgp log-neighbor-changes
router-1(config-router)# neighbor 27.1.1.1 remote-as 2
router-1(config-router)# neighbor 27.1.1.1 update-source Loopback0
router-1(config-router)# no auto-summary
router-1(config-router)# exit

For GB Service Destined to AS5

Create a distinct route map for this service. This includes setting the next-hop of packets matching
29.1.1.1 so they will be mapped onto Tunnel #1 (the guaranteed bandwidth service tunnel). At the device
level:
router-1(config)# route-map set-qos-group permit 10
router-1(config-route-map)# match as-path 100
router-1(config-route-map)# set ip qos-group 6
router-1(config-route-map)# set ip next-hop 29.1.1.1
router-1(config-route-map)# exit
router-1(config)# ip as-path access-list 100 permit ^5$

For GB Service Transiting through AS5

Create a distinct route map for this service. (Its traffic will go to AS6 and AS7).
At the device level:
router-1(config)# route-map set-qos-group permit 10
router-1(config-route-map)# match as-path 101
router-1(config-route-map)# set ip qos-group 6
router-1(config-route-map)# set ip next-hop 29.1.1.1
router-1(config-route-map)# exit
router-1(config)# ip as-path access-list 101 permit _5_

For GB Service Destined to Community 100:1

Create a distinct route map for all traffic destined to prefixes that have community value 100:1. This
traffic will go to AS3, AS5, and AS8.
At the device level:
router-1(config)# route-map set-qos-group permit 10
router-1(config-route-map)# match community 20
router-1(config-route-map)# set ip qos-group 6
router-1(config-route-map)# set ip next-hop 29.1.1.1
router-1(config-route-map)# exit
router-1(config)# ip community-list 20 permit 100:1

Mapping Traffic onto the Tunnels

Map all guaranteed bandwidth traffic onto Tunnel #1:

router-1(config)# ip route 29.1.1.1 255.255.255.255 Tunnel1

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Map all best-effort traffic onto Tunnel #2:

router-1(config)# ip route 30.1.1.1 255.255.255.255 Tunnel2

Configuration of Tunnel Head-2

As with the Head-1 device and interfaces, the following Head-2 configuration first presents commands
that establish a sub-pool tunnel (commands presented earlier on page 13) and then also configures a
global pool tunnel. After that it presents QoS and BGP commands that guarantee end-to-end service on
the sub-pool tunnel. (Because this is a 7500 (VIP) router, Modular QoS CLI is used).

Configuring the Pools and Tunnels

At the device level:

router-2(config)# ip cef distributed
router-2(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-2(config)# router isis router ospf 100
router-2(config-router)# net redistribute connected
49.0000.1000.0000.0011.00
router-2(config-router)# metric-style wide network 11.1.1.0 0.0.0.255 area 0
router-2(config-router)# is-type level-1 network 22.1.1.1 0.0.0.0 area 0
router-2(config-router)# mpls traffic-eng level-1 mpls traffic-eng area 0
[now one resumes the common command set]:
router-2(config-router)# mpls traffic-eng router-id Loopback0
router-2(config-router)# exit

Create a virtual interface:

router-2(config)# interface Loopback0
router-2(config-if)# ip address 22.1.1.1 255.255.255.255
router-2(config-if)# exit

At the outgoing physical interface:

router-2(config)# interface pos0/0
router-2(config-if)# ip address 11.1.1.1 255.0.0.0
router-2(config-if)# mpls traffic-eng tunnels
router-2(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 60000
[and if using IS-IS instead of OSPF]:
router-2(config-if)# ip router isis
[and in all cases]:
router-2(config-if)# exit

At one tunnel interface, create a sub-pool tunnel:

router-2(config)# interface Tunnel3
router-2(config-if)# ip unnumbered Loopback0
router-2(config-if)# tunnel destination 27.1.1.1
router-2(config-if)# tunnel mode mpls traffic-eng
router-2(config-if)# tunnel mpls traffic-eng priority 0 0
router-2(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 30000
router-2(config-if)# tunnel mpls traffic-eng path-option 1 explicit name gbs-path2
router-2(config-if)# exit

and at a second tunnel interface, create a global pool tunnel:

router-2(config)# interface Tunnel4
router-2(config-if)# ip unnumbered Loopback0

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router-2(config-if)# tunnel destination 27.1.1.1

router-2(config-if)# tunnel mode mpls traffic-eng
router-2(config-if)# tunnel mpls traffic-eng priority 0 0
router-2(config-if)# tunnel mpls traffic-eng bandwidth 70000
router-2(config-if)# tunnel mpls traffic-eng path-option 1 explicit name \
best-effort-path2
router-2(config-if)# exit

In this example explicit paths are used instead of dynamic, to ensure that best-effort traffic and
guaranteed bandwidth traffic will travel along different paths.
At the device level:
router-2(config)# ip explicit-path name gbs-path2
router-2(config-ip-expl-path)# next-address 24.1.1.1
router-2(config-ip-expl-path)# next-address 27.1.1.1
router-2(config-ip-expl-path)# exit
router-2(config)# ip explicit-path name best-effort-path2
router-2(config-ip-expl-path)# next-address 24.1.1.1
router-2(config-ip-expl-path)# next-address 25.1.1.1
router-2(config-ip-expl-path)# next-address 27.1.1.1
router-2(config-ip-expl-path)# exit

Note that autoroute is not used, as that could cause the Interior Gateway Protocol (IGP) to send other
traffic down these tunnels.

Configuring DiffServ QoS

At the inbound physical interface (in Figure 3 this is FE2/1), packets received are rate-limited to:
a. a rate of 30 Mbps
b. a normal burst of 1 MB
c. a maximum burst of 2 MB
Packets that are mapped to qos-group 6 and that conform to the rate-limit are marked with experimental
value 5 and the BGP destination community string, and are forwarded; packets that do not conform
(exceed action) are dropped:
router-2(config)# interface FastEthernet2/1
router-2(config-if)# rate-limit input qos-group 6 30000000 1000000 2000000 \
conform-action set-mpls-exp-transmit 5 exceed-action drop
router-2(config-if)# bgp-policy destination ip-qos-map
router-1(config-if)# exit

At the device level create a class of traffic called “exp5-class” that has MPLS experimental bit set to 5:
router-2(config)# class-map match-all exp5-class
router-2(config-cmap)# match mpls experimental 5
router-2(config-cmap)# exit

Create a policy that creates a priority queue for “exp5-class”:

router-2(config)# policy-map core-out-policy
router-2(config-pmap)# class exp5-class
router-2(config-pmap-c)# priority 100000
router-2(config-pmap-c)# exit
router-2(config-pmap)# class class-default
router-2(config-pmap-c)# bandwidth 55000
router-2(config-pmap-c)# exit
router-2(config-pmap)# exit

The policy is applied to packets exiting interface POS0/0:

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interface POS0/0
service-policy output core-out-policy

As a result of all the above configuration lines, packets entering the Head-2 router via interface FE2/1
and destined for AS5, BGP community 100:1, or transiting AS5 will have their experimental field set to
5. It is assumed that no other packets entering this router (on any interface) are using this exp bit value.
(If this cannot be assumed, an additional configuration must be added to mark all such packets with
another experimental value.) When exiting this router via interface POS0/0, packets marked with
experimental value 5 are placed into the priority queue.

Note Packets entering the router via FE2/1 and exiting through POS0/0 enter as IP packets and exit as
MPLS packets.

Configuring QoS Policy Propagation via BGP

For All GB Services

Create a table map under BGP to map (tie) the prefixes to a qos-group. At the device level:
router-2(config)# ip bgp-community new-format
router-2(config)# router bgp 2
router-2(config-router)# no synchronization
router-2(config-router)# table-map set-qos-group
router-2(config-router)# bgp log-neighbor-changes
router-2(config-router)# neighbor 27.1.1.1 remote-as 2
router-2(config-router)# neighbor 27.1.1.1 update-source Loopback0
router-2(config-router)# no auto-summary
router-2(config-router)# exit

For GB Service Destined to AS5

Create a distinct route map for this service. This includes setting the next-hop of packets matching
29.1.1.1 so they will be mapped onto Tunnel #3 (the guaranteed bandwidth service tunnel). At the device
level:
router-2(config)# route-map set-qos-group permit 10
router-2(config-route-map)# match as-path 100
router-2(config-route-map)# set ip qos-group 6
router-2(config-route-map)# set ip next-hop 29.1.1.1
router-2(config-route-map)# exit
router-2(config)# ip as-path access-list 100 permit ^5$

For GB Service Transiting through AS5

Create a distinct route map for this service. (Its traffic will go to AS6 and AS7).
At the device level:
router-2(config)# route-map set-qos-group permit 10
router-2(config-route-map)# match as-path 101
router-2(config-route-map)# set ip qos-group 6
router-2(config-route-map)# set ip next-hop 29.1.1.1
router-2(config-route-map)# exit
router-2(config)# ip as-path access-list 101 permit _5_

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

For GB Service Destined to Community 100:1

Create a distinct route map for all traffic destined to prefixes that have community value 100:1. This
traffic will go to AS3, AS5, and AS8.
At the device level:
router-2(config)# route-map set-qos-group permit 10
router-2(config-route-map)# match community 20
router-2(config-route-map)# set ip qos-group 6
router-2(config-route-map)# set ip next-hop 29.1.1.1
router-2(config-route-map)# exit
router-2(config)# ip community-list 20 permit 100:1

Mapping the Traffic onto the Tunnels

Map all guaranteed bandwidth traffic onto Tunnel #3:

router-2(config)# ip route 29.1.1.1 255.255.255.255 Tunnel3

Map all best-effort traffic onto Tunnel #4:

router-2(config)# ip route 30.1.1.1 255.255.255.255 Tunnel4

Tunnel Midpoint Configuration [Mid-1]

All four interfaces on the midpoint router are configured very much like the outbound interface of the
head router. The strategy is to have all mid-point routers in this Autonomous System ready to carry future
as well as presently configured sub-pool and global pool tunnels.

Configuring the Pools and Tunnels

At the device level:

router-3(config)# ip cef distributed
router-3(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-3(config)# router isis router ospf 100
router-3(config-router)# net redistribute connected
49.0000.2400.0000.0011.00
router-3(config-router)# metric-style wide network 10.1.1.0 0.0.0.255 area 0
router-3(config-router)# is-type level-1 network 11.1.1.0 0.0.0.255 area 0
router-3(config-router)# mpls traffic-eng network 24.1.1.1 0.0.0.0 area 0
level-1
router-3(config-router)# network 12.1.1.0 0.0.0.255 area 0
router-3(config-router)# network 13.1.1.0 0.0.0.255 area 0
router-3(config-router)# mpls traffic-eng area 0
[now one resumes the common command set]:
router-3(config-router)# mpls traffic-eng router-id Loopback0
router-3(config-router)# exit

Create a virtual interface:

router-3(config)# interface Loopback0
router-3(config-if)# ip address 24.1.1.1 255.255.255.255
router-3(config-if)# exit

At the physical interface level (ingress):

router-3(config)# interface pos2/1
router-3(config-if)# ip address 10.1.1.2 255.0.0.0

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Configuration Examples

router-3(config-if)# mpls traffic-eng tunnels

router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

router-3(config)# interface pos1/1

router-3(config-if)# ip address 11.1.1.2 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

At the physical interface level (egress), through which two sub-pool tunnels currently exit:
router-3(config)# interface pos3/1
router-3(config-if)# ip address 12.1.1.1 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

At the physical interface level (egress), through which two global pool tunnels currently exit:
router-3(config)# interface pos4/1
router-3(config-if)# ip address 13.1.1.1 255.0.0.0
router-3(config-if)# mpls traffic-eng tunnels
router-3(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-3(config-if)# ip router isis
[and in all cases]:
router-3(config-if)# exit

Tunnel Midpoint Configuration [Mid-2]

Both interfaces on this midpoint router are configured like the outbound interfaces of the Mid-1 router.

Configuring the Pools and Tunnels

At the device level:

router-5(config)# ip cef distributed
router-5(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right]:
router-5(config)# router isis router ospf 100
router-5(config-router)# net redistribute connected
49.2500.1000.0000.0012.00
router-5(config-router)# metric-style wide network 13.1.1.0 0.0.0.255 area 0
router-5(config-router)# is-type level-1 network 14.1.1.0 0.0.0.255 area 0
router-5(config-router)# mpls traffic-eng level-1 network 25.1.1.1 0.0.0.0 area 0
router-5(config-router)# mpls traffic-eng area 0
[now one resumes the common command set]:
router-5(config-router)# mpls traffic-eng router-id Loopback0
router-5(config-router)# exit

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

Create a virtual interface:

router-5(config)# interface Loopback0
router-5(config-if)# ip address 25.1.1.1 255.255.255.255
router-5(config-if)# exit

At the physical interface level (ingress):

router-5(config)# interface pos1/1
router-5(config-if)# ip address 13.1.1.2 255.0.0.0
router-5(config-if)# mpls traffic-eng tunnels
router-5(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-5(config-if)# ip router isis
[and in all cases]:
router-5(config-if)# exit

At the physical interface level (egress):

router-5(config)# interface pos2/1
router-5(config-if)# ip address 14.1.1.1 255.0.0.0
router-5(config-if)# mpls traffic-eng tunnels
router-5(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-5(config-if)# ip router isis
[and in all cases]:
router-5(config-if)# exit

Tunnel Tail Configuration

The inbound interfaces on the tail router are configured much like the outbound interfaces of the
midpoint routers:

Configuring the Pools and Tunnels

At the device level:

router-4(config)# ip cef distributed
router-4(config)# mpls traffic-eng tunnels
[now one uses either the IS-IS commands on the left or the OSPF commands on the right. In the case
of OSPF, one must advertise two new loopback interfaces—29.1.1.1 and 30.1.1.1 in our
example—which are defined in the QoS Policy Propagation section, further along on this page]:
router-4(config)# router isis router ospf 100
router-4(config-router)# net redistribute connected
49.0000.2700.0000.0000.00
router-4(config-router)# metric-style wide network 12.1.1.0 0.0.0.255 area 0
router-4(config-router)# is-type level-1 network 14.1.1.0 0.0.0.255 area 0
router-4(config-router)# mpls traffic-eng level-1 network 27.1.1.1 0.0.0.0 area 0
router-4(config-router)# network 29.1.1.1 0.0.0.0 area 0
router-4(config-router)# network 30.1.1.1 0.0.0.0 area 0
router-4(config-router)# mpls traffic-eng area 0
[now one resumes the common command set, taking care to include the two additional loopback
interfaces]:
router-4(config-router)# mpls traffic-eng router-id Loopback0
router-4(config-router)# mpls traffic-eng router-id Loopback1
router-4(config-router)# mpls traffic-eng router-id Loopback2

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Configuration Examples

router-4(config-router)# exit

Create a virtual interface:

router-4(config)# interface Loopback0
router-4(config-if)# ip address 27.1.1.1 255.255.255.255
router-4(config-if)# exit

At the physical interface (ingress):

router-4(config)# interface pos2/1
router-4(config-if)# ip address 12.1.1.2 255.0.0.0
router-4(config-if)# mpls traffic-eng tunnels
router-4(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:
router-4(config-if)# exit

router-4(config)# interface pos2/2

router-4(config-if)# ip address 14.1.1.2 255.0.0.0
router-4(config-if)# mpls traffic-eng tunnels
router-4(config-if)# ip rsvp bandwidth 140000 140000 sub-pool 70000
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:
router-4(config-if)# exit

Configuring QoS Policy Propagation

On the tail device, one must configure a separate virtual loopback IP address for each class-of-service
terminating here. The headend routers need these addresses to map traffic into the proper tunnels. In the
current example, four tunnels terminate on the same tail device but they represent only two service
classes, so only two additional loopback addresses are needed:
Create two virtual interfaces:
router-4(config)# interface Loopback1
router-4(config-if)# ip address 29.1.1.1 255.255.255.255
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:
router-4(config-if)# exit
router-4(config)# interface Loopback2
router-4(config-if)# ip address 30.1.1.1 255.255.255.255
[and if using IS-IS instead of OSPF]:
router-4(config-if)# ip router isis
[and in all cases]:
router-4(config-if)# exit

At the device level, configure BGP to send the community to each tunnel head:
router-4(config)# ip bgp-community new-format
router-4(config)# router bgp 2
router-4(config-router)# neighbor 23.1.1.1 send-community
router-4(config-router)# neighbor 22.1.1.1 send-community
router-4(config-router)# exit

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MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Command Reference

Command Reference
This section documents only commands that are new or modified.
• ip rsvp bandwidth
• mpls traffic-eng ds-te bc-model
• mpls traffic-eng ds-te mode
• show mpls traffic-eng topology
• tunnel mpls traffic-eng bandwidth

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
ip rsvp bandwidth

ip rsvp bandwidth
To enable Resource Reservation Protocol (RSVP) for IP on an interface, use the ip rsvp bandwidth
command in interface configuration mode. To disable RSVP completely, use the no form of this
command. To eliminate only the subpool portion of the bandwidth, use the no form of this command
with the sub-pool keyword.

ip rsvp bandwidth [interface-kbps] [single-flow-kbps] [ [rdm kbps {[subpool kbps] | [bc1

subpool]}] | [mam max-reservable-bw kbps bc0 kbps bc1 kbps] ]

no ip rsvp bandwidth [interface-kbps] [single-flow-kbps] [ [rdm kbps {[subpool kbps] | [bc1

subpool]}] | [mam max-reservable-bw kbps bc0 kbps bc1 kbps] ]

Syntax Description interface-kbps (Optional) Maximum amount of bandwidth, in kbps, that may be allocated
by RSVP flows. The range is from 1 to 10,000,000.
single-flow-kbps (Optional) Maximum amount of bandwidth, in kbps, that may be allocated
to a single flow. The range is from 1 to 10,000,000. [This value is ignored by
the Diff-Serv-aware MPLS Traffic Engineering feature].
rdm kbps Russian Doll Model for DiffServ-aware traffic engineering. The keyword is
optional.
subpool kbps This keyword and value are used in the traditional (pre-IETF-Standard)
implementation of DS-TE to specify the amount of bandwidth, in kbps, on
the interface that is to be reserved to a portion of the total. The range is from
1 to the value of the smaller of the interface-kbps and rdm kbps arguments.
bc1 subpool This keyword and value are used in the IETF-Standard implementation of
DS-TE to specify the same bandwidth portion as subpool kbps, namely the
amount of bandwidth, in kbps, on the interface that is to be reserved to a
portion of the total. The range is from 1 to the value of the smaller of the
interface-kbps and rdm kbps arguments.
mam Maximum Allocation Model for DiffServ-aware traffic engineering.
max-reservable-bw The maximum reservable bandwidth — this sets a limit on the size of the
kbps total pool.
bc0 kbps Amount of bandwidth, in kbps, on the interface to be reserved to the total
(formerly called “global pool”). The range is from 1 to the value of the
max-reservable-bw kbps argument.
bc1 kbps Amount of bandwidth, in kbps, on the interface to be reserved to a portion of
the total. (Formerly this portion was called the “subpool”). The range is from
1 to the value of the max-reservable-bw kbps argument.

Defaults RSVP is disabled by default.

If the ip rsvp bandwidth command is entered but no bandwidth values are supplied (for example,
ip rsvp bandwidth is entered followed by pressing the Enter key), a default bandwidth value (that is,
75% of the link bandwidth) is assumed for both the interface-kbps and single-flow-kbps arguments.

Command Modes Interface configuration

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
ip rsvp bandwidth

Command History Release Modification

11.2 This command was introduced.
12.0(11)ST This command was integrated into Cisco IOS Release 12.0(11)ST, and the
sub-pool keyword was added.
12.2(4)T This command was integrated into Cisco IOS Release 12.2(4)T. This
command was implemented on the Cisco 7500 series and the
ATM-permanent virtual circuit (PVC) interface.
12.2(14)S This command was integrated into Cisco IOS Release 12.2(14)S.
12.2(18)S This command was integrated into Cisco IOS Release 12.2(18)S.
12.2(18)SXD This command was integrated into Cisco IOS Release 12.2(18)SX.
12.2(28)SB This command was integrated into Cisco IOS Release 12.2(28)SB.
12.2(33)SRA This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(33)SRB The IETF Standard for DiffServ-aware traffic engineering (DS-TE) was
added through the keyword alternatives rdm (Russian Dolls Model) and
mam (Maximum Allocation Model), and their subsidiary arguments.

Usage Guidelines RSVP cannot be configured with distributed Cisco Express Forwarding (dCEF).
RSVP is disabled by default to allow backward compatibility with systems that do not implement RSVP.
Weighted Random Early Detection (WRED) or fair queueing must be enabled first.
When you issue the ip rsvp bandwidth command, the RSVP bandwidth pool adjusts dynamically when
the bandwidth of the interface changes.
When using this command for DiffServ-aware traffic engineering (DS-TE) in IETF Standard mode, you
must use either rdm and its arguments or mam and its arguments; you cannot use both. For more details
about each alternative, see Russian Dolls Bandwidth Constraints Model for Diffserv-aware MPLS Traffic
Engineering ed. by F. Le Faucheur (RFC 4127) and Maximum Allocation Bandwidth Constraints Model
for Diffserv-aware MPLS Traffic Engineering by F. Le Faucheur & W. Lai (RFC 4125).

Examples The following example shows a T1 (1536 kbps) link configured to permit RSVP reservation of up to
1158 kbps, but no more than 100 kbps for any given flow on serial interface 0. Fair queueing is
configured with 15 reservable queues to support those reserved flows, should they be required.
Router(config)# interface serial 0
Router(config-if)# fair-queue 64 256 15
Router(config-if)# ip rsvp bandwidth 1158 100

Related Commands Command Description

fair-queue (WFQ) Enables WFQ for an interface.
ip rsvp neighbor Enables neighbors to request a reservation.
ip rsvp reservation Enables a router to behave like it is receiving and forwarding RSVP RESV
messages.
ip rsvp sender Enables a router to behave like it is receiving and forwarding RSVP PATH
messages.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
ip rsvp bandwidth

Command Description
ip rsvp udp-multicasts Instructs the router to generate UDP-encapsulated RSVP multicasts
whenever it generates an IP-encapsulated multicast packet.
random-detect Enables WRED or DWRED.
(interface)
show ip rsvp installed Displays RSVP-related installed filters and corresponding bandwidth
information.
show ip rsvp interface Displays RSVP-related interface information.
show ip rsvp neighbor Displays current RSVP neighbors.
show ip rsvp Displays RSVP-related receiver information currently in the database.
reservation
show ip rsvp sender Displays RSVP PATH-related sender information currently in the
database.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
mpls traffic-eng ds-te bc-model

mpls traffic-eng ds-te bc-model

To enable a Bandwidth Constraints Model to be used by a router in DiffServ-aware Traffic Engineering,
use the mpls traffic-eng ds-te bc-model global configuration command. (Using the no form of this
command selects the default model, which is the Russian Dolls Model.)

mpls traffic-eng ds-te bc-model [rdm | mam]

no mpls traffic-eng ds-te bc-model [ rdm | mam ]

Syntax Description rdm Russian Dolls Model. (Described in IETF RFC 4127).
mam Maximum Allocation Model. (Described in IETF RFC 4125).

Defaults Russian Dolls Model is the default.

Command Modes Global configuration

Command History Release Modification

12.2(33)SRB This command was introduced.

Usage Guidelines 1. The Maximum Allocation Model should be selected when the network administrator needs to ensure
isolation across all Class Types without having to use pre-emption, and can afford to risk some QoS
degradation of Class Types other than the Preimum Class.
2. The Russian Dolls Model should be selected when the network administrator needs to prevent QoS
degradation of all Class Types and can impose pre-emption.

Examples In the following example,the Maximum Allocation Model is being selected:

Router(config)# mpls traffic-eng ds-te bc-model mam

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
mpls traffic-eng ds-te mode

mpls traffic-eng ds-te mode

To configure a router to enter DiffServ-aware Traffic Engineering modes which incorporate degrees of
the IETF Standard, use the mpls traffic-eng ds-te mode global configuration command. Use the no form
of this command to return the router to the pre-IETF-Standard mode.

mpls traffic-eng ds-te mode [migration | ietf]

no mpls traffic-eng ds-te mode [migration | ietf ]

Syntax Description migration A mode by which the router generates IGP and tunnel signalling according to the
pre-IETF standard, but adds TE-class mapping and accepts advertisement in both the
pre-IETF and the IETF-Standard formats.
ietf The “Liberal” IETF mode, by which the router generates IGP advertisement and tunnel
signalling according to the IETF Standard and responds to TE-class mapping, yet also
accepts advertisement in both the pre-IETF-Standard and IETF-Standard formats.

Defaults Pre-IETF-Standard mode is the default.

Command Modes Global configuration

Command History Release Modification

12.2(33)SRB This command was introduced.

Usage Guidelines 1. Place the router into Migration Mode only if it is still in the pre-IETF Standard (“Traditional”)
mode, and you want to begin upgrading its network to operate the IETF-Standard form of DS-TE.
2. Place the router into Liberal-IETF Mode only if its network is already in the Migration Mode, and
you want to complete the upgrade of that network so it will operate the IETF-Standard form of
DS-TE.

Examples In the following example, the router is configured to operate in Migration Mode:
Router(config)# mpls traffic-eng ds-te migration

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
show mpls traffic-eng topology

show mpls traffic-eng topology

To display the MPLS traffic engineering global topology as currently known at this node, use the show
mpls traffic-eng topology command in privileged EXEC mode.

show mpls traffic-eng topology {A.B.C.D | igp-id {isis nsapaddr | ospf A.B.C.D}} [brief]
[model-id{mam | rdm}]

Syntax Description A.B.C.D Specifies the node by the IP address (router identifier to interface
address).
igp-id Specifies the node by IGP router identifier.
isis nsapaddr Specifies the node by router identification (nsapaddr) if using IS-IS.
ospf A.B.C.D Specifies the node by router identifier if using OSPF.
brief (Optional) Provides a less detailed version of the topology.
model-id {mam | rdm } Shows topology based on a Bandwidth Constraints Model: either the
Maximum Allocation Model (mam) or the Russian Dolls Model
(rdm).

Command Modes Privileged EXEC

Command History Release Modification

12.0(5)S This command was introduced.
12.0(11)ST The single “Reservable” column was replaced by two columns: one each for
“global pool” and for “subpool.”
12.2(8)T This command was integrated into Cisco IOS Release 12.2(8)T.
12.2(14)S This command integrated into Cisco IOS Release 12.2(14)S.
12.2(28)SB This command was implemented on Cisco 10000(PRE-2) routers.
12.2(33)SRA This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(33)SRB The command was updated to display IETF-Standard bandwidth constraints
model information.

Examples The following example shows output from the show mpls traffic-eng topology command:
Router# show mpls traffic-eng topology

My_System_id: 0000.0000.0001.00 (isis 1 level-2)

My_System_id: 10.10.10.10 (ospf 100 area 0)
My_BC_Model_Type: MAM

Signalling error holddown: 10 sec Global Link Generation 56

IGP Id: 0000.0000.0001.00, MPLS TE Id: 10.10.10.10 Router Node (isis 1 level-2)

Link[0]:Point-to-Point, Nbr IGP Id:0000.0000.0002.00, Nbr Node Id:6, gen:56

Frag Id:0, Intf Address:7.2.2.1, Intf Id:0
Nbr Intf Address:7.2.2.2, Nbr Intf Id:0

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
show mpls traffic-eng topology

TE Metric:10, IGP Metric:10, Attribute Flags:0x0

Switching Capability:, Encoding:
BC Model ID:MAM
Physical BW:155520 (kbps), Max Reservable BW:1000 (kbps)
BC0:600 (kbps) BC1:400 (kbps)
Total Allocated Reservable
BW (kbps) BW (kbps)
--------------- -----------
TE-class[0]: 0 600
TE-class[1]: 0 400
TE-class[2]: 0 0
TE-class[3]: 0 0
TE-class[4]: 0 600
TE-class[5]: 0 400
TE-class[6]: 0 0
TE-class[7]: 0 0

Link[1]:Point-to-Point, Nbr IGP Id:0000.0000.0002.00, Nbr Node Id:6, gen:56

Frag Id:0, Intf Address:7.1.1.1, Intf Id:0
Nbr Intf Address:7.1.1.2, Nbr Intf Id:0
TE Metric:10, IGP Metric:10, Attribute Flags:0x0
Switching Capability:, Encoding:
BC Model ID:MAM
Physical BW:155520 (kbps), Max Reservable BW:1000 (kbps)
BC0:600 (kbps) BC1:400 (kbps)
Total Allocated Reservable
BW (kbps) BW (kbps)
--------------- -----------
TE-class[0]: 10 590
TE-class[1]: 0 400
TE-class[2]: 0 0
TE-class[3]: 0 0
TE-class[4]: 0 600
TE-class[5]: 0 400
TE-class[6]: 0 0
TE-class[7]: 0 0

Table 3 describes significant fields shown in the display.

Table 3 show mpls traffic-eng topology Field Descriptions

Field Description
My_System_id Unique identifier of the IGP.
My_BC_Model_Type Bandwidth constraints model of the local node.
IGP Id Identification of the advertising router.
MPLS TE Id Unique MPLS traffic engineering node identifier.
Router Node/Network Node Type of Node
Intf Address The interface address of the link.
Nbr IGP Id Neighbor IGP router identifier.
gen Generation number of the link-state packet (LSP). This internal
number is incremented when any new LSP is received.
FragId GP LSA fragment identifier.
TE Metric TE cost of the link.
IGP Metric IGP cost of the link.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
show mpls traffic-eng topology

Table 3 show mpls traffic-eng topology Field Descriptions (continued)

Attribute Flags The requirements on the attributes of the links that the traffic crosses.
Physical BW Physical line rate.
Max Reservable BW Maximum amount of bandwidth that can be reserved on a link.
Total Allocated Amount of bandwidth allocated at that priority.
Reservable Amount of available bandwidth reservable for that TE-Class for two
pools: BC0 (formerly called “global” and BC1 (formerly called
“sub”).

Related Commands Command Description

show mpls traffic-eng tunnels Displays information about tunnels.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
tunnel mpls traffic-eng bandwidth

tunnel mpls traffic-eng bandwidth

To configure bandwidth required for an MPLS traffic engineering tunnel, use the tunnel mpls
traffic-eng bandwidth command in interface configuration mode. To disable this feature, use the no
form of this command.

tunnel mpls traffic-eng bandwidth [sub-pool | class-type1] bandwidth

no tunnel mpls traffic-eng bandwidth [sub-pool | class-type1] bandwidth

Syntax Description sub-pool (Optional) Indicates a sub-pool tunnel.

class-type1 (Optional) IETF-Standard syntax to indicate a sub-pool tunnel.
bandwidth The bandwidth, in kilobits per second, set aside for the MPLS traffic
engineering tunnel. Range is between 1 and 4294967295 .

Defaults Default bandwidth is 0.

Default is a global pool tunnel.

Command Modes Interface configuration

Command History Release Modification

12.0(5)S This command was introduced.
12.0(11)ST Sub-pool option was added.
12.2(33)SRB Class-type1 keyword was added and global keyword was eliminated.

Usage Guidelines Enter the bandwidth for either a global pool (BC0) or sub-pool (BC1) tunnel, not both in the same
statement. To specify both pools, you need to use this command twice, once with the sub-pool or
class-type1 keyword to specify the narrower tunnel, and once without those keywords to specify the
larger tunnel.

Related Commands Command Description

show mpls traffic-eng tunnel Displays information about tunnels.

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MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Glossary

Glossary
This section defines acronyms and words that may not be readily understood.
AS—Autonomous System. A collection of networks under a common administration, sharing a common
routing strategy and identified by a unique 16-bit number (assigned by the Internet Assigned Numbers
Authority).
BGP—Border Gateway Protocol. The predominant interdomain routing protocol. It is defined by RFC 1163.
Version 4 uses route aggregation mechanisms to reduce the size of routing tables.
CBR—Constraint Based Routing. The computation of traffic paths that simultaneously satisfy
label-switched path attributes and current network resource limitations.
CEF—Cisco Express Forwarding. A means for accelerating the forwarding of packets within a router, by
storing route lookup information in several data structures instead of in a route cache.
CLI—Command Line Interface. Cisco’s interface for configuring and managing its routers.
DS-TE—Diff Serv-aware Traffic Engineering. The capability to configure two bandwidth pools on each
link, a global pool and a sub-pool. MPLS traffic engineering tunnels using the sub-pool bandwidth can
be configured with Quality of Service mechanisms to deliver guaranteed bandwidth services end-to-end
across the network. Simultaneously, tunnels using the global pool can convey DiffServ traffic.
flooding—A traffic passing technique used by switches and bridges in which traffic received on an
interface is sent out through all of the interfaces of that device except the interface on which the
information was originally received.
GB queue—Guaranteed Bandwidth queue. A per-hop behavior (PHB) used exclusively by the strict
guarantee traffic. If delay/jitter guarantees are sought, the diffserv Expedited Forwarding queue
(EF PHB) is used. If only bandwidth guarantees are sought, the diffserv Assured Forwarding PHB
(AF PHB) is used.
Global Pool—The total bandwidth allocated to an MPLS traffic engineering link.
IGP—Interior Gateway Protocol. An internet protocol used to exchange routing information within an
autonomous system. Examples of common internet IGPs include IGRP, OSPF, and RIP.
label-switched path (LSP) tunnel—A configured connection between two routers, using label
switching to carry the packets.
IS-IS—Intermediate System-to-Intermediate System. A link-state hierarchical routing protocol, based on
DECnet Phase V routing, whereby nodes exchange routing information based on a single metric, to determine
network topology.
LCAC—Link-level (per-hop) call admission control.
LSP—Label-switched path (see above).
Also Link-state packet—A broadcast packet used by link-state protocols that contains information about
neighbors and path costs. LSPs are used by the receiving routers to maintain their routing tables. Also called
link-state advertisement (LSA).
MPLS—Multi-Protocol Label Switching (formerly known as Tag Switching). A method for directing
packets primarily through Layer 2 switching rather than Layer 3 routing, by assigning the packets short
fixed-length labels at the ingress to an MPLS cloud, using the concept of forwarding equivalence classes.
Within the MPLS domain, the labels are used to make forwarding decisions mostly without recourse to the
original packet headers.
MPLS TE—MPLS Traffic Engineering (formerly known as “RRR” or Resource Reservation Routing). The
use of label switching to improve traffic performance along with an efficient use of network resources.

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 MPLS Traffic Engineering—DiffServ Aware (DS-TE)
Glossary

OSPF—Open Shortest Path First. A link-state, hierarchical IGP routing algorithm, derived from the IS-IS
protocol. OSPF features include least-cost routing, multipath routing, and load balancing.
RSVP—Resource reSerVation Protocol. An IETF protocol used for signaling requests (to set aside
internet services) by a customer before that customer is permitted to transmit data over that portion of
the network.
Sub-pool—The more restrictive bandwidth in an MPLS traffic engineering link. The sub-pool is a
portion of the link’s overall global pool bandwidth.
TE—Traffic engineering. The application of scientific principles and technology to measure, model, and
control internet traffic in order to simultaneously optimize traffic performance and network resource
utilization.

Note See Internetworking Terms and Acronyms for terms not included in this glossary.

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