UNIT-II

3G AND 4G CELLULAR NETWORKS

Migration to 3G Networks – IMT 2000 and UMTS – UMTS

Architecture – User Equipment –Radio Network Subsystem –
UTRAN – Node B – RNC functions – USIM – Protocol Stack –
CS and PS Domains – IMS Architecture – Handover – 3.5G and
3.9G a brief discussion –4G LAN and Cellular Networks – LTE –
Control Plane – NAS and RRC – User Plane –PDCP, RLC and
MAC – WiMax IEEE 802.16d/e – WiMax Internetworking with
3GPP

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 Migration to 3G Networks
Why 3G?
• Existing mobile networks (GSM/CDMA) were designed to
handle voice traffic and voice-oriented services.
• Then, when they were introduced into the market it turned
out that, other than voice-oriented, additional services
(SMS to set an example) gained unexpected popularity.
• The need for data transmission through mobile networks
has been growing gradually together with Internet
popularity.
• Therefore some network upgrades had to be
introduced into existing mobile networks (HSCSD,
GPRS).
• However, these improvements provide only limited
capability (e.g. GPRS - up to 50kbit/s in reality). They
don't provide flexible, variable data speed,
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supporting Quality of Service solutions.

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 3G Vision
Some 3G advantages :
 - Multimedia (voice, data & video) exchanging .
 -Increased data rates
 -384 Kbps while moving
 -2 Mbps when stationary at specific
 Locations
 - Universal global roaming
 Multilevel data rates which gives multi-purpose
networking .
 Many different applications .
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 First Generation
• Advanced Mobile Phone Service (AMPS)
– US trials 1978; deployed in Japan (’79) & US (’83)
– 800 MHz band — two 20 MHz bands
– TIA-553
– Still widely used in US and many parts of the world
• Nordic Mobile Telephony (NMT)
– Sweden, Norway, Demark & Finland
– Launched 1981; now largely retired
– 450 MHz; later at 900 MHz (NMT900)
• Total Access Communications System (TACS)
– British design; similar to AMPS; deployed 1985
– Some TACS-900 systems still in use in Europe

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 Second Generation — 2G
• Digital systems
• Leverage technology to increase capacity
– Speech compression; digital signal processing
• Utilize/extend “Intelligent Network” concepts
• Improve fraud prevention
• Add new services
• There are a wide diversity of 2G systems
– IS-54/ IS-136 North American TDMA; PDC (Japan)
– iDEN
– DECT and PHS
– IS-95 CDMA (cdmaOne)
– GSM

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 Migration to 3G Networks
Data Rates
2 Mbps

1 Mbps 3G
(144Kbps to 2Mbps)

100 Kbps
2.5G
(10-150Kbps)
10 Kbps
2G
(9.6Kbps)
1 Kbps
1G
(<1Kbps)

1980 1990
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Years
2000

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Migration To 3G

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 Cellular networks: From 1G to 3G
• 1G: First generation wireless cellular: Early 1980s
– Analog transmission, primarily speech: AMPS (Advanced
Mobile Phone Systems) and others
• 2G: Second generation wireless cellular: Late 1980s
– Digital transmission
– Primarily speech and low bit-rate data (9.6 Kbps)
– High-tier: GSM, IS-95 (CDMA), etc
– Low-tier (PCS): Low-cost, low-power, low-mobility e.g. PACS
• 2.5G: 2G evolved to medium rate (< 100kbps) data
• 3G: future Broadband multimedia
– 144 kbps - 384 kbps for high-mobility, high coverage
– 2 Mbps for low-mobility and low coverage
• Beyond 3G: research in 4G

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 IMT 2000
What is IMT 2000?
• IMT-2000 is
3G
• 3G is a term coined by the global cellular community to
indicate the next generation of mobile service capabilities, e.g.,
higher capacity and enhanced network functionalities, which
allow advanced services and applications, including
multimedia.
• IMT-2000 (International Mobile Telecommunications-2000) is
the ITU globally coordinated definition of 3G covering key
issues such as frequency spectrum use and technical
standards .
• Multiple radio technology options have been included in the
IMT-2000 standard to allow seamless service evolution from
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the various 2G mobile standards that are extensively deployed
around the world.

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 IMT-2000 Terrestrial Radio Interfaces
Recommendation ITU-R M.1457:
Detailed Specifications of the Radio Interfaces of IMT-2000

Paired Unpaired
spectrum

IMT-DS IMT-MC IMT-TC IMT-SC IMT-FT

W-CDMA cdma2000 UTRAN UWC- DECT
(UTRAN FDD) TDD TD- 136
Direct Multi SCDMA (EDGE)
Frequenc
Spread Carrier Time Single y Time
Code Carrier

CDMA TDMA
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 IMT-2000 is much more
IMT-2000 systems are expected to provide support for :
- high transmission data rates for indoor and outdoor operations
- symmetrical and asymmetrical data transmission
- circuit-switched and packet-switched services, such as
Internet Protocol (IP) traffic and real-time video
- voice quality comparable to wire-line quality
- greater capacity and improved spectrum efficiency
- several simultaneous services to end-users and terminals,
for multimedia services
- global, i.e. international, roaming between different
operational environments
- economies of scale through open global standards to meet the
needs of the mass market.
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 UMTS

• Universal Mobile Telecommunications System (UMTS)

• UMTS is an upgrade from GSM via GPRS
• The standardization work for UMTS is carried out by
Third Generation Partnership Project (3GPP)
• Data rates of UMTS are:
– 144 kbps for rural
– 384 kbps for urban outdoor
– 2048 kbps for indoor and low range outdoor

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 UMTS Frequency Spectrum

• UMTS Band
– 1900-2025 MHz and 2110-2200 MHz for 3G
transmission
– In the US, 1710–1755 MHz and 2110–2155 MHz
will be used instead, as the 1900 MHz band was
already used.

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 UMTS Architecture

A UMTS network consist of three interacting domains;

1. Core Network (CN),
2. UMTS Terrestrial Radio Access Network (UTRAN) and
3. User Equipment (UE).
The main function of the core network is to provide switching,
routing and transit for user traffic. Core network also
contains the databases and network management functions.
The basic Core Network architecture for UMTS is based on
GSM network with GPRS. All equipment has to be modified for
UMTS operation and services. The UTRAN provides the air
interface access method for User Equipment. Base Station is
referred as Node-B and control equipment for Node-B's is called
Radio Network Controller (RNC). UMTS system page has an
example, how UMTS network could be build.
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1. Core Network (CN)
The main function of the core network is to provide
switching, routing and transit for user traffic. Core network
also contains the databases and network management
functions.
2. UTRAN
UMTS Terrestrial Radio Access Network (UTRAN):
Provides the air interface access method for user equipment
3. User Equipment (UE):
Terminals work as air interface counterpart for base
stations. The various identities are: IMSI, TMSI, P-TMSI,
TLLI, MSISDN, IMEI, IMEISV

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UMTS - Architecture

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 UMTS – Architecture

• MS -Mobile Station
USIM – UMTS Subscriber Identity Module
• UTRAN - UMTS Terrestrial Radio Access Network
- RNS - Radio Network Subsystem
RNC - Radio Network Controller
Node B - Base station
• Network node
UMSC - UMTS Mobile Switching Center
Registers
• GMSC- Gateway Services Switching Center

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 UMTS – frequency spectrum

• Up/Downlink Frequency
Uplink: 1920 - 1980MHz
Downlink: 2110 -
2170MHz
• Own sub band for satellite service:
Uplink: 1980 MHz to 2010 MHz
Downlink: 2170 MHz to 2200 MHz

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 UMTS - Advantages

• Broad offer of services

• Speed, variety and user-friendliness of
a service significantly improved compared with GSM.
• Only bearer services are standardized
• Actual application is called teleservice

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 UMTS - teleservices

• Teleservice created individually by a

• service provider using bearer services.
• Only 4 teleservices standardized:
• Speech
• Fax
• SMS
• Emergency call

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 UMTS - Applications

• Fast Internet / Intranet

• Streaming / Download (Video, Audio)
• Videoconferences
• Multimedia-Messaging, E-Mail
• Mobile E-Commerce (M-Commerce)
• Location Based Services
• Mobile Entertainment (Games,…)

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 User Equipment
• The UMTS standard does not restrict the functionality of
the User Equipment in any way. Terminals work as an air
interface counter part for Node-B and have many
different types of identities. Most of these UMTS identity
types are taken directly from GSM specifications.
• International Mobile Subscriber Identity (IMSI)
• Temporary Mobile Subscriber Identity (TMSI)
• Packet Temporary Mobile Subscriber Identity
(P- TMSI)
• Temporary Logical Link Identity (TLLI)

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 User Equipment(con…)
• Mobile station ISDN (MSISDN)
• International Mobile Station Equipment Identity (IMEI)
• International Mobile Station Equipment Identity
and Software Number (IMEISV)

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 User Equipment
The user equipment is sub-divided into:
• Mobile Equipment Domain (ME): Performs radio
transmission and contains applications. It consists of:
– Mobile termination (MT): Radio transmission and
related functions.
– Terminal Equipment (TE): Contains end-to-
end applications.
• User Identity Module Domain (USIM): Contains data and
procedures which unambiguously and securely identify itself.

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 User Equipment

MT
USIM

TE ME
UE

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 Radio Network Subsystem
• Every Radio Network Subsystem is managed by Radio
Network Controller (RNC)
Key RNSAP Functions:
• Radio Link
• Management (between SRNC and DRNC)
• Reconfiguration (between SRNC and DRNC)
• Supervision (reports from DRNC to SRNC)
• Common Control Channel (CCCH) Signalling Transfer
• Paging
• Relocation Execution

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 UTRAN

UTRAN (Universal Terrestrial Radio Access Network) is the

radio access network in UMTS.
UTRAN consists of a set of Radio Network Subsystems (RNS)
connected to Core Network.

RNS
RNC RNC

Node B Node B

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– A RNS consists of the Radio Network Controller (RNC)
and one or more Node Bs. Each RNS is responsible for
the resources of its set of cells.
– RNC is responsible for the handover decisions that
require signalling to the UE. It is equivalent to BSC in
GSM network.
– Node B is responsible for radio transmission/reception
in one or more cells to/from UE. It is equivalent to BTS
in GSM network.

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 UTRAN architecture
B RNS

UE1 Node Iub

B
RNC
UE2

Node
Node
B
UE3

Iur
Node
Iub
BNode
RNC

RNS
Node
Node
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RNC: e
No re
Radio f
de qu
Networ o
B iri
r
k can ng
sup h sig
Controll nal
por a
er RNS: t n ing
Radio FD d to
D o th
Networ v e
or
k TD e UE
Subsyst D r
or d Ce
em Iu bot ll
e
h c off C
i ers
UTRAN RN s FD
compris C is i D
es res o or
several pon n TD
RNSs sibl s D
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 Node B

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 RNC functions

• The functions of RNC are:

Radio Resource
Control Admission
Control Channel
Allocation Power
Control Settings
Handover Control
Macro Diversity
Ciphering
Segmentation / Reassembly
Broadcast Signalling
Open Loop Power Control

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SEM/ 3
 USIM Protocol Stack
• A Universal Subscriber Identity Module is an application
for UMTS mobile telephony running on a UICC (Universal
Integrated Circuit Card ) smart card which is inserted in a
3G mobile phone.
• There is a common misconception to call the UICC card
itself a USIM, but the USIM is merely a logical entity on the
physical card.

• It stores user subscriber information, authentication

information and provides storage space for text messages
and phone book contacts. The phone book on a UICC has
been greatly enhanced.

• For authentication purposes, the USIM stores a long-term

preshared secret key K, which is shared with the
Authentication Center (AuC) in the network.

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• The USIM also verifies a sequence number that must be within
a range using a window mechanism to avoid replay attacks,
and is in charge of generating the session keys CK and IK to
be used in the confidentiality and integrity algorithms of the
KASUMI block cipher in UMTS.

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 Circuit switched (CS) domain

• The CS domain comprises all network functionality

for provision of bearer and teleservices in a circuit
orientated manner, meaning the control protocols
(e.g. call handling) are based on circuit switched
control protocols

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 Packet switched(PS) domain

• the PS domain comprises all network functionality

for provision of bearers in a packet orientated
manner, meaning the control protocols (e.g. call
handling) are based on packet switched control
protocols

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 IMS

• IMS is an architecture, it is not a protocol.

• Open-systems architecture that supports a range of IP-

based services over both Private and Carrier networks,
employing both wireless and fixed access technologies.

• IMS is defined by 3GPP.

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 Basic Principles

• Access Independence
• Different Network Architectures
• Terminal and user mobility
• Extensive IP-based services

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 IMS Building Blocks

1. An all-IP Core Network (CN)

2. An all-IP Radio Access network (RAN)
3. Multimedia call control based on SIP
4. Quality of Service (QoS) support for IP

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 IMS Architecture
Application Layer
SIP / OSA / CAMEL
AS AS
Control Layer
Management
MRF

SIP, IP
HSS

CSCF Provisioning
SG/MGCF

Connectivity & Access Layer Charging

MGW
IP/MPLS PSTN/PLMN

GERAN, UTRAN, WLAN, xDSL,...

Number Mapping

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HSS: Home Subscriber Server
CSCF: Call Session Control MRFP: Multimedia Resource
Function:
S-CSCF: Serving CSCF
I- CSCF: Interrogating
CSCF P-CSCF: Proxy
CSCF
BGCF: Breakout Gateway
Control Function
MGCF: Media Gateway
Control Function
AS: Application Server
SCP: Service Control Point
MGW: Media Gateway
MRFC: Multimedia Resource
Function Controller

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IMS
Architecture

SGW
Applicatio ns and Services
Operator 1 Operator 2 Multimed ia IP Network

HSS CSCF BGCF

IM -SSF
BGCF CS
OSA-SCS
Domain
CSCF
MGCF MG W or -
PSTN
AS W
SG
or - Legacy

SCP MRFC MRFP

- or -
External
GGSN
Mobile Alternati ve Access Netwo

GERAN
UE SGSN
UTRAN

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 Vertical vs. Horizontal Architecture

ice
vice

S vic 1

3
vice
Common functions

e e

S 2
r

e
r
Network logic Routing

Terminal Terminal Network

Terminal logic Terminal

Replicated - not reusable Replication of common functions

Application logic
Common functions
Routing

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 Who needs IMS?
Fixed Network Users want
• Multimedia Conferencing
• Voice over IP
• Streaming Services

Mobile Network Users want

• Push-to-X
• Location Based Services
• Mobile Gaming

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Network Providers want

• Fixed Mobile Convergence

• One service - one implementation for all
access types
• New Business Models

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 Problems and open issues

• Architecture complexity.
• Guarantees of QoS.
• IETF and 3GPP standardisation co-operation.
• SIP and IMS architecture are not mature enough to
guarantee fully functioning network.
• Terminal complexity.

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 There is still work to be done....

• The current work in 3GPP is still unfinished and the

discussion with IETF has just been started.

• The specification work still continue now.

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 Handover

• Handover basically means changing the point of connection

while communicating.
• Old Concept
• Whenever Mobile Station is connected to 1 BaseStation and
there is a need to change to anotherBase Station, it is known as
HANDOVER.

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New Concept
• When mobile station switches from one set of radio resources
to another set, HANDOVER is said to have taken place. Radio
resources Radio resources Set I Set II HANDOVER

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 HANDOFF DECISIONS

• There are numerous methods for performing handoff.

From the decision process point of view, one can find
at least three different kinds of handoff decisions.
• Network-Controlled Handoff
• Mobile-Assisted Handoff
• Mobile-Controlled Handoff

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Network-Controlled Handoff:
• In a network-controlled handoff protocol, the network
makes a handoff decision based on the measurements of the
MSs at a number of BSs.
• In general, the handoff process takes 100–200 ms.
• Network-controlled handoff is used in first-generation
analog systems such as AMPS (Advanced Mobile Phone
System), TACS(Total Access Communication System), and
NMT (Nordic Mobile Telephone).

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Mobile-Assisted Handoff
• In a mobile-assisted handoff process, the MS
makes measurements and the network makes the
decision.
• In the circuit-switched GSM (global system mobile), the
BS controller (BSC) is in charge of the radio interface
management. This mainly means allocation and release
of radio channels and handoff management.
• The handoff time between handoff decision and execution
in a circuit- switched GSM is approximately 1 second.

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Mobile-Controlled Handoff

• In mobile-controlled handoff, each MS is completely

in control of the handoff process.
• This type of handoff has a short reaction time (in the order
of 0.1 second).
• MS measures the signal strengths from surrounding BSs
and interference levels on all channels.
• A handoff can be initiated if the signal strength of the
serving BS is lower than that of another BS by a certain
threshold.

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 TYPES OF HANDOVER

• HARD HANDOVER
• SOFT HANDOVER
• HORIZONTAL HANDOVER
• VERTICAL HANDOVER

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 HARD HANDOVER

“BREAK BEFORE MAKE”•

• Old connection is broken before a new connection
is activated
• Primarily used in FDMA and TDMA systems (e.g. GSM)
• Different frequency ranges used in adjacent cells to
minimize the interference

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 Mechanism of Hard Handover

• The base station BS1 on one cell site hands off the mobile
station(MS)’s callto another cell BS2.
• The link to the prior base station, BS1 is terminated before
the user istransferred to the new cell’s base station, BS2.
The MS is linked to no morethan one BS at any given time.

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CHARACTERISTICS
• A Hard handover is relatively cheaper and easier to
implement in comparison to other types of
Handover.
• It is primarily used in FDMA (frequency division multiple
access) and TDMA (time division multiple access), where
different frequency ranges are used in adjacent channels
in order to minimize channel interference.
• It is simpler as phones hardware does not need to be
capable of receiving two or more channels in
parallel.

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INTER-CELL AND INTRA-CELL HANDOVER

• The inter-cell handover switches a call in progressfrom

one cell to another cell, and the intra-cellhandover
switches a call in progress from one physicalchannel of a
cell to another physical channel of thesame cell.

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 SOFT HANDOVER

“MAKE BEFORE BREAK”

• New connection is activated before the old is broken
• Used in UMTS to improve the signal quality •
• Uplink and downlink signals may be combined for
better signal
• A mobile may in UMTS spend a large part of
the connection time in soft handover
• Better connection reliability•
• More seamless handover.

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MECHANISM OF SOFT HANDOVER

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• The call is first connected to the new base station BS2 and
then it is dropped by the previous base station BS1.
• The call will be established only when a reliable
connection to the target cell is obtained. The MS is linked
to two BS for a brief interval of time. Thus soft handover
involves connection to more than one cell.

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CHARACTERISTICS

• It offers more reliable access continuity in network

connection and less chances of a call termination during
switching of base stations in comparison to a Hard handoff.
• It is commonly used in CDMA (Code-division multiple
access) systems that enables the overlapping of the repeater
coverage zones, so that every cell phone set is always well
within range of at least one of the base stations.
• Technical implementation of a Soft handoff is more
expensive and complex in comparison to a Hard handoff.
• It is used in sensitive communication services such as
videoconferencing.

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 SOFTER HANDOVER

• Softer handover is the situation where one base

station receives two user signals from two adjacent
sectors it serves.
• In the case of softer handover the base station receives
2 separated signals through multi-path propagation.
• Due to reflections on buildings or natural barriers
the signal sent from the mobile stations reaches the
base station from two different sectors.

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IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 6
 HORIZONTAL HANDOVER
Horizontal handover is when a mobile terminal changes its
point of connection within the same type of network
• E.g. from a cell to another in GSM
• E.g. from an access point to another in
WiFi• Reasons for handover
• Worse signal quality or loss of signal
• Traffic load balancing
• Cost

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IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 6
 VERTICAL HANDOVER

• Vertical handover or vertical handoff refers to a

network node changing the type of connectivity it uses to
access a supporting infrastructure, usually to support
node mobility
• Vertical handovers refer to the automatic fall over
from one technology to another in order to maintain
communication.

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IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 7
CAPABILITIES OF VERTICAL HANDOVER AS
COMPARED TO HORIZONTAL HANDOVER
• Usage of different access technologies
• Usage of multiple network interfaces
• Usage of multiple IP addresses
• Usage of multiple (changeable) QoS parameters
• Usage of multiple network connections (multi-homing
features)

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SEM/ 7
 HANDOFF FAILURES

• Because frequencies cannot be reused in adjacent cells,

when a user moves from one cell to another, a new
frequency must be allocated for the call.
• If a user moves into a cell when all available channels are
in use, the user’s call must be terminated.
• Problem of signal interference where adjacent cells
overpower each other resulting in receiver
desensitization is also there.

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SEM/ 7
 3.5G
(HSDPA)High Speed Downlink Packet Access

Why HSDPA?
• Increasing bit rates in downlink.

• Reducing delay ”TTI”.

• Efficient users scheduling.

• Simultaneaous single carrier support for UMTS and

R5 HSDPA

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 7
 Why HSDPA?

 Comparison Between 3G & 3.5G.

 Data Rate ( 2Mbps -----> 10 Mbps)

 Modulation ( QPSK -----> QPSK&16QAM)

 TTI( 10ms ----> 2ms )

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SEM/ 7
 How HSDPA  HSDPA Features
• Decreasing delay due to transmission errors

Hybrid Automatic Repeat Request

H-ARQ Schemes
• Chase combining

• Incremental Redundancy

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7
SEM/
 Chase Combining

Data Block
Accept
Combine
Data Block
Retransmissions
Block

• Coding is applied to transmission packets

• Soft combining of original and retransmitted signals
is done at receiver before decoding
• Advantage:
self decodable, time diversity, path diversity
• Disadvantage:
wastage of bandwidth
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 7
 Incremental Redundancy

IR
Error Database
Data Block
Error
Combin Detection

Information Accept
No Error Data Block
from IR database

Deliver To
Upper
Layers

• Advantage:
Reducing the effective data throughput/bandwidth of a user and
using this for another user
• Disadvantage:
non-self decodable
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
7
SEM/
 How HSDPA  HSDPA Features

• Decreasing delay due to transmission errors

Hybrid Automatic Repeat Request

• Decreasing HO failure

Fast cell site selection

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SEM/ 7
 Fast cell site selection (FCS)

• 20 to 30% of UE on soft handover

• Tracking of active set of Node B‘s connected to a UE

• Selection of the Node-B with the best current transmission

characteristics

• High data rates can be achieved

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7
SEM/
 Additional Physical Channels

• High Speed Physical Downlink

Shared Channel (HS-PDSCH)

– HS-Downlink Shared Channel

(HS-DSCH)

– HS-Shared Control Channel (HS-

SCCH)

• High Speed Dedicated Physical

Control Channel (HS-DPCCH)

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

7
SEM/
 How HSDPA  HSDPA Features

• Decreasing delay due to transmission errors

Hybrid Automatic Repeat Request

• Decreasing HO failure

Fast cell site selection

• Improving resources management

Stand alone downlink shared channel

• Adapting to environment local features

Adaptive Modulation and Coding

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 7
 AMC

• Modulation Schemes:

– QPSK

– 16QAM

• Code Rates used:

– 1/4, 1/2, 5/8 and ¾

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

8
SEM/
HSDPA EVOLUTION

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 8
 HSDPA Terminals
• New terminals are required to take advantage of HSDPA:

– PC-cards will be the first on the market

– In the 1st phase terminals will offer:

• Download 3,6 Mbps end user throughput

• Upload 384 kbps

– Hand-held terminals will follow

– In a 2nd phase, peak data rates are increased to:

• Download 14 Mbps

• Upload 384 kbps

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I SEM/
NE7002/MPC/UNIT-II/PPT/VERSION 1.1 82
 Conclusion

• The most changing from 3G to the 3.5G is the modulation.

• More efficient implementation of interactive and

background Quality of Service (QoS) classes

• Peak data rates exceeding 2 Mbps and theoretically 10

Mbps & more with MIMO

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SEM/ 83
 3.9G(LTE)
• LTE stands for Long Term Evolution
• The goal of LTE (3.9G) is to provide a high-data-rate,
low- latency and packet-optimized radio access technology
supporting flexible bandwidth deployments.
• In parallel, new network architecture is designed with
the goal to support packet-switched traffic with seamless
mobility, quality of service and minimal latency.
• Next Generation mobile broadband technology
• Promises data transfer rates of 100 Mbps
• Based on UMTS 3G technology
• Optimized for All-IP traffic

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SEM/ 84
Advantages of LTE

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SEM/ 85
Comparison of LTE Speed

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SEM/ 86
 Major LTE Radio Technologies

• Uses Orthogonal Frequency Division Multiplexing

(OFDM) for downlink
• Uses Single Carrier Frequency Division Multiple
Access (SC-FDMA) for uplink
• Uses Multi-input Multi-output(MIMO) for
enhanced throughput
• Reduced power consumption
• Higher RF power amplifier efficiency (less battery
power used by handsets)

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SEM/ 87
LTE Architecture

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SEM/ 88
Control-plane protocol Stack

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SEM/ 89
• RLC and MAC sublayers (terminated in eNB on the
network side) perform the same functions as for the user
plane
• The various functions performed by RRC (terminated in
eNB on the network side) are
- Broadcast
- Paging
- RRC connection management
- Mobility functions
- UE measurement reporting and control.
• PDCP sublayer performs
- Integrity Protection
- Ciphering.

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SEM/ 90
• NAS (terminated in aGW on the network side) performs
- SAE bearer management
- Authentication
- Idle mode mobility handling
- Paging origination
- Security control for the signaling between aGW and
UE, and for the user plane.

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SEM/ 91
 4G LAN

•4G technologies are sometimes referred to by the

acronym “MAGIC” which stands for Mobile
multimedia, Anytime/any-where, Global mobility
support, Integrated wireless and Customized personal
service.
•Use your wireless device anywhere for listening to
music, shopping (m-commerce) , downloading (file
transfer), watching video (live streaming)
•Multiple applications (talk and use Internet services
at the same time)

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SEM/ 92
 4G Technology Challenges
– Supporting heterogeneous multitude of systems
• Includes multiple networks:
• Cellular telecommunication systems
• Digital video broadband
• Digital audio broadband
– Wireless LAB, Bluethood-based networks
– Open communication network: infrastructure
independent which can access to any services and
applications (now and in the future!)
– Complete compatibility between wireless and wired
networks through gateways

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SEM/ 93
 4G Technology Challenges(con..)

– Supporting statistical multiplexing of

heterogeneous data over-the-air
– Latency, noisy environment,
unpredictable discontinuities and loss, etc.
– High-speed wireless transmission over the air
• High performance physical layer
– 20Mbps (2G: 28Kbps, 3G: 2Mbps)
• Scarce bandwidth availability
• Efficient frequency spectrum utilization
• Efficient hand off
• Dynamic bandwidth allocation
• Advanced digital transmission technology
(modulation, low power devices, etc.)
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SEM/ 94
 Current Technology
• TDMA :Time Division Multiple Access, is a technique
for dividing the time domain up into sub channels for
use by multiple devices.
• CDMA :Code Division Multiple Access, allows every
device in a cell to transmit over the entire bandwidth at all
times.

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SEM/ 95
 4G Hardware

• Ultra Wide Band Networks : Ultra Wideband technology,

or UWB, is an advanced transmission technology that can be
used in the implementation of a 4G network.
• Smart Antennas : Multiple “smart antennas” can be
employed to help find, tune, and turn up signal information

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SEM/ 96
 General 4G Services and 4G Applications

• Localized/Personalized Information
• Organizational services
• Communications services and applications
• Entertainment services
• Mobile commerce (M-Commerce ) User

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SEM/ 97
 Features of 4G Wireless Systems

• Support interactive multimedia

• User friendliness
• High speed, high capacity and low cost per bit
• Higher band widths
• Terminal Heterogeneity
• Network Heterogeneity

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SEM/ 98
 User and Industry Expectations

Wireless users can be categorized into generalized segments :

• The Age segment
• The Internet Usage segment
• The Mobile Professional segment

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SEM/ 99
Comparison between 3g and 4g

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Conclusion

• 4G will be a Convergence Platform providing clear

advantages in terms of Coverage, Bandwidth, Power
Consumption, variety of Services, ranging from Pop-
Up advertisements to Location-Based services and IP
Data casting ones.

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Cellular Networks
Principles of Cellular Networks
• Underlying technology for mobile phones, personal
communication systems, wireless networking etc.
• Developed for mobile radio telephone
– Replace high power transmitter/receiver systems
• Typical support for 25 channels over 80km
– Use lower power, shorter range, more transmitters

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Cellular Network Organization
• Multiple low power transmitters
– 100w or less
• Area divided into cells
– Each with own antenna
– Each with own range of frequencies
– Served by base station
• Transmitter, receiver, control unit
– Adjacent cells on different frequencies to
avoid crosstalk

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SEM/ 10
 Shape of Cells
• Square
• Hexagon

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SEM/ 10
Cellular Geometries

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Frequency Reuse
• Power of base transceiver controlled
– Allow communications within cell on given frequency
– Limit escaping power to adjacent cells
– Allow re-use of frequencies in nearby cells
– Use same frequency for multiple conversations
– 10 – 50 frequencies per cell
• E.g.
– N cells all using same number of frequencies
– K total number of frequencies used in systems
– Each cell has K/N frequencies
– Advanced Mobile Phone Service (AMPS) K=395,
N=7 giving 57 frequencies per cell on average

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SEM/ 10
Frequency Reuse Patterns

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Increasing Capacity (1)
• Add new channels
– Not all channels used to start with
• Frequency borrowing
– Taken from adjacent cells by congested cells
– Or assign frequencies dynamically
• Cell splitting
– Non-uniform distribution of topography and traffic
– Smaller cells in high use areas
• Original cells 6.5 – 13 km
• 1.5 km limit in general
• More frequent handoff
• More base stations

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SEM/ 10
Cell Splitting

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 10
 Increasing Capacity (2)
• Cell Sectoring
– Cell divided into wedge shaped sectors
– 3 – 6 sectors per cell
– Each with own channel set
• Subsets of cell’s channels
– Directional antennas
• Microcells
– Move antennas from tops of hills and large buildings
to tops of small buildings and sides of large buildings
• Even lamp posts
– Form microcells
– Reduced power
– Good for city streets, along roads and inside
large buildings
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SEM/ 11
Frequency Reuse Example

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
 Operation of Cellular Systems
• Base station (BS) at center of each cell
– Antenna, controller, transceivers
• Controller handles call process
– Number of mobile units may in use at a time
• BS connected to mobile telecommunications switching office
(MTSO)
– One MTSO serves multiple BS
– MTSO to BS link by wire or wireless
• MTSO:
– Connects calls between mobile units and from mobile
to fixed telecommunications network
– Assigns voice channel
– Performs handoffs
– Monitors calls (billing)
• Fully IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 11
Overview of Cellular System

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
 Channels

• Control channels
– Setting up and maintaining calls
– Establish relationship between mobile unit and
nearest BS
• Traffic channels
– Carry voice and data

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SEM/ 11
 Long Term Evolution (LTE)

• What is LTE?
• LTE is the next generation of Mobile
broadband technology
• Data rates of 100 Mbps
• It is the next level after UMTS 3G technology
• Works with IP

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
 Advantages

• Provides low latency

• Higher network throughput
• Increased data transfer speed
• More cost effectiveness
• Improvements over 3G network

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
LTE v/s Other technologies

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
 LTE Technologies

OFDM (Orthogonal Frequency Division Multiplexing) for

downlink SC-FDMA (Single Carrier – Frequency Division Multiple
Access)
for uplink
MIMO (Multiple Input Multiple Output)
SAE (System Architecture Evolution)

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 11
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 11
 LTE Network Elements
-Evolved Node B (eNB)
 Supports air interface
 Provides radio resource management functions
-Serving Gateway (SGW)
 Provides Mobility
 Responsible for Routing and Forwarding
-Packet Data Network Gateway (PDN GW)
 Provides connectivity to Internet
 Provides QoS and mobility between 3G and non-
3G networks
-Mobility Management Entity (MME)
 Manages mobility and provides security
 Operates in control plane and provides authentication

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
 LTE Future and Uses

 Mass deployment to begin around 2012

 Devices which are covered under LTE are – Mobile
phones, laptops, cameras, camcorders
 Assured interoperability with older wireless
technologies such as GSM, WCDMA/HSPA, CDMA,
TD-SCDMA

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
 LTE Advanced
• Mobile Communication Standard
As a major enhancement of the 3GPP LTE
Standard
• Peak data rates of 1 Gbps to meet IMT
Advanced standards for 4G
• Ability to leverage advanced topology
heterogenous networks such as Picocells
and Femtocells
• Improves capacity and coverage and
provides large bandwidth upto 100 MHz of
spectrum
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 12
 Control Plane

• Protocols for controlling the radio access bearers and

the connection between the UE and the network
• Has three layers: physical layer, data-link layer
and network layer.
• Data link layer comprises of MAC and RLC. Network
layer comprises of RRC ,MM,GMM and CM.
• RLC,MAC and PHY are also present in USER PLANE.

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 12
NAS(Network Attached Storage)

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
• In the past, floppy drives with capacities in mere KB’s
were widely used to share data files. Over time the need
for larger and larger capacity has emerged due to growing
need for data to be shared across organizations.
Removable storage media, such as flash drives, are
capable of storing gigabytes (GB) of data have now
complimented the traditional removable media drives.
• Businesses not only need the capacity to handle huge data
storage requirements, the need to share their data has
made Network Attached Storage (NAS) an attractive
option. NAS systems use external storage for server/hosts,
adding flexibility to network storage. NAS works at the file
level, rather than the block level. This enables widespread
access to the data over the network, based upon the file
system client loaded.

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 12
 What is NAS
• NAS is shared storage on a network infrastructure using
a unique addressing schema. A NAS server is a storage
device that consists of a high performance file server and
attached to a LAN. It is a single-purpose machine serving
as a dedicated, high-performance, high-speed
communication gateway to file data.
• Note: A NAS device is sometimes called an appliance or
filer.
• The NAS head (as illustrated) could be remote from its
storage (gateway) or contained within the same cabinet
as its storage—so that the storage is dedicated to NAS
applications (integrated).

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 12
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 12
• Unlike a general-purpose server, such as a Unix or NT
server, a NAS server is a device optimized for file
serving functions such as storing, retrieving, and serving
files. A single function NAS device provides:
– Real-time OS dedicated to file serving
– Open standard protocols
– Built-in native clustering for high availability

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SEM/ 13
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 13
• The following are some benefits of NAS:
– Supports global information access
• Enables greater file sharing, even over a
long distance
• Supports many-to-one or one-to-many
configurations
• Can share data across platforms
– Improves efficiency through specialized OS, optimized
for file serving
• Eliminates bottlenecks encountered when
accessing files from central file server
• Relieves

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SEM/ 13
– Flexibility - works with many types of clients on
both UNIX and Microsoft Windows platforms using
Industry standard protocols.
– Centralizes storage – minimizes duplication on
client workstations, reducing management
complexity and improving data protection.
– Simplifies management - leverages existing security
infrastructure through standard network protocols.
Single point of management for multiple systems for
multiple data sets. Identifies data by file name and
byte offsets, transfers file data or file meta-data.
– Scalable - Due to its high performance, low latency
design, enables NAS to scale well and depending upon
utilization profiles, address many differing types of
business applications.

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SEM/ 13
– High availability
• Replication and recovery options
• Can safely centralize large amounts of user
data behind a single NAS device with
redundant networking equipment to provide
maximum connectivity options.
• Clustering technology for failover in the event
of filer failure
– Handles security, user authentication, and file locking in

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SEM/ 13
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 13
• A NAS device is made up of the following components:
– Network Interface via one or more Network
Interface Cards (NICs)
• Examples: Gigabit Ethernet (1000 Mb/s), Fast
Ethernet (10Mb/s), ATM, and FDDI.
– Network File Systems (NFS) and Common Internet File
Systems (CIFS) protocols
– Proprietary, optimized Windows, UNIX, or
LINUX based OS. Examples:
• DART - Data Access in Real Time (EMC)
• Data ONTAP (Network Appliance)
– Industry standard storage protocols to connect to and
manage physical disk storage resources.
• Examples: Serial ATA (SATA), SCSI, or
Fibre Channel
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 13
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 13
• Most NAS devices support multi-protocol file services to
handle file I/O requests to the remote file system. The
more common protocols for file sharing are:
– Network File Systems (NFS) - developed by Sun and
closely aligned with UNIX-based operating systems
– Common Internet File Systems (CIFS) – developed by
Microsoft and closely aligned with Windows-based
operating systems

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 13
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 13
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
• While CIFS and NFS are file system protocols, it is
important to understand how the network transport
protocols of IP, TCP, and FTP fit into the picture.
– OSI model (developed by the ISO standards body) -
defines the specific layers that are responsible for
communication tasks.
– Internet Protocol Suite – defines a group of open-
system (non-proprietary) protocols that communicate
across interconnected networks (LAN/WAN). This suite
includes both low layer protocols (e.g., IP and TCP) as
well as common applications such as electronic mail,
terminal emulation, and file transfer (FTP).

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 14
• IP is a network-layer protocol that
contains addressing information and some
control information, enabling packets to be
routed.
• In NAS, the back-end connects to its storage most
often using Fibre Channel interconnectivity and the
front-end/client connectivity most often via the
TCP/IP protocol. If any client wants to access a file
from NAS system, it requests the file directly. The
NAS system then converts this request in block
level access and retrieves data from storage and
presents data to client as a complete file.

IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 14
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
• NFS and CIFS protocols handle file I/O requests to the
remote file system, which is managed by the NAS device.
– I/O requests are packaged by the requestor into TCP/IP and
forwarded through the network stack, transported across
the network, and received by the NAS.
– The NAS converts the protocol request into an appropriate
physical storage request (block I/O), and then performs
the operation against the physical storage pool.
– The data returned from the physical storage pool is then
processed by the NAS and repackaged into an
appropriate file protocol response.
– This response is packaged into TCP/IP again and
forwarded through the network to the client.
• This example shows an operation being directed to the remote
NAS device and how the different protocols and software
layers play a part in moving the request and response between
client and IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
the

client and IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I

SEM/ 14
Due to the structure of the specialized operating system on
NAS devices, multiple protocol stacks can be simultaneously
supported, thereby allowing disparate systems access to the
storage simultaneously.

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SEM/ 14
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
 Radio Resource Control (RRC)
• Used for setting up, reconfigure and reestablish
radio bearers.
• • Cell Broadcast Service (CBS) control.
• • Initial cell selection and cell re-selection.
• • Paging.
• • Broadcast of information:
• – related to the non-access stratum (Core Network).
• – related to the access stratum.
• • Establishment, maintenance and release
• – of an RRC connection between the UE and UTRAN.
• – of Radio Bearers.
IFETCE/M.E (CSE) /RAJESH.R/I YEAR/I
SEM/ 14
• Assignment, reconfiguration and release of radio
resources for the RRC connection.
• Control of requested QoS.
• UE measurement reporting and control of the reporting.
• RRC message integrity protection.
• Arbitration of radio resources on uplink DCH.
• Slow Dynamic Channel Allocation (DCA) (TDD mode).
• Timing advance (TDD mode).
• RRC connection mobility functions (RNC relocation).
• Outer loop power control.
• Control of ciphering.

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RRC logical architecture

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• Dedicated Control Functional Entity (DCFE): Handles
functions and signalling specific to UE. One DCFE entity
for each UE
• Paging and Notification control Functional Entity (PNFE):
paging of idle mode UE. At least one PNFE in the RNC for
each cell..
• Broadcasting Control Functional Entity (BCFE): handles
the broadcasting of system information. There is at least
one BCFE for each cell in the RNC.

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RRC states and state transitions including GSM

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 RRC service states
• Idle Mode:
– After UE is switched on it will camp in the a suitable
cell. After camping:
– User is able to send and receive system and
cell broadcasting information.
– In the idle mode until it transmits a request to
establish RRC connection.
• Cell_DCH
– Entered from Idle Mode or by establishing a DCH from
the Cell_FACH state.
– DPCH and physical downlink shared channel (PDSCH) is
allocated to UE.
– UE is in this mode until explicit signalling for Cell_FACH.
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• Cell_FACH
– No dedicated channel allocated. Data transmitted
through RACH and FACH.
– UE listens BCH.
– Cell reselection is performed (RNC is informed).
• Cell_PCH
– UE known at a cell level but can be reached via PCH.
– Usel listens BCH, some terminals also BMC.
– In case of Cell reselection automatically moved to
Cell_FACH state.

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• URA_PCH
– UE executes the cell update procedure only if the
UTRAN Registration Area is changed.
– DCCH can not be used in this state, all the activities
initiated by the network through the
PCCH or RACH.

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User-plane Protocol Stack

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RLC and MAC sublayers (terminated in eNB on the network
side) perform the following functions
- Scheduling
- ARQ
- HARQ
PDCP (Packet Data Convergence Protocol) sublayer
(terminated in aGW on the network side) performs for the
user plane the following functions
- Header Compression
- Integrity Protection
- Ciphering.

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 PDCP
• PDCP is Packet Data Convergence Protocol.
• It is one of the layers of the Radio Traffic Stack in
UMTS and performs IP header compression and
decompression, transfer of user data and maintenance of
sequence numbers for Radio Bearers which are
configured for lossless serving radio network subsystem
(SRNS) relocation.
• The compression technique can be based on either
RFC 2507 or RFC 3095.
• RFC 1144 can also be used for some background
information, and although the techniques in the RFC are
not used in modern TCP/IP implementations, it still
shows what the compression/decompression technique
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looks like.

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• If PDCP is configured for No Compression it will send the
IP Packets without compression; otherwise it will
compress the packets according to its configuration by
upper layer and attach a PDCP header and send the
packet.
• It uses the service provided by a lower layer called
Radio Link Control (RLC) that uses the Radio Link
Protocol.
• PDCP header consists of two fields: PID and PDU TYPE.
• PDU Type field indicates whether the PDU is Data PDU
or Sequence Number PDU.
• PID field value indicates header compression protocol
type used and packet type or CID.

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 (RLC)Radio Link Control
•The main functions of the layer are segmentation and
reassembly of RLC top layer of packages in order to
adapt them to the size that can be effectively
transmitted over the radio interface.
•For radio bearers which are in need of transmission
errors, the RLC is relayed to discover how to
recover from packet losses.
•In addition, the RLC Reordering performed to
compensate for out-of-order Receipt due to hybrid
automatic repeat request (HARQ) Layer below. There
is only one entity per RLC radio spokesman.

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 MAC (Medium Access Control) layer
• This layer performs the multiplexing of data for a variety
of radio carriers.
• Therefore, it is not only one of the MAC for the UE.
• Determining the amount of data that can be transmitted
from each radio bearer layer, the size of the packet,
RLC and instructing on the MAC layer to achieve
negotiated Quality of Service (QoS) for each radio
bearer.
• Uplink, this process involves communication of the
amount of data to transfer the eNodeB
• On the sending side, each layer receives a data service unit
(SDU) from the higher layers, layer provides services and
outputs the Protocol data unit (PDU) to the lower layer. A
layer of RLC receives packets from PDCP layers. These
packages are called PDUs with the PDCP point of view, and
represent the PDCP RLC SDUs perspective, RLC. A layer of
RLC creates packages that are scheduled for the layer
below, i.e., the MAC layer.
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 IEEE/802.16/WiMAX technologies
• Attractive emerging metropolitan technology for rural and
• metropolitan area broadband wireless access (BWA)
• highly efficient and suitable to support a large range of
applications
• for residential and enterprise environments
• officially named as the WirelessMAN™)
• IEEE 802.16x - basic standards
• WiMAX
• "Worldwide Interoperability for Microwave Access”
- alternative name
• given by industry group WiMAX Forum
• WiMAX Forum mission : promote and certify compatibility
and
• interoperability of broadband wireless products
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 WiMax IEEE 802.16d/e
Background of IEEE 802.16
• 1998: IEEE 802 SG on “Broadband Wireless Access”
(BWA) (Prof. Roger B. Mark, Chair, IEEE 802.16 WG,
Jan. 2001)
– 1999: 1st IEEE 802.16 Project
– Scope: PHY and MAC layer of the air interface of
interoperable fixed point-to-multipoint broadband wireless
access systems. The specification enables transport of data,
video, and voice services. It applies to systems operating
in the vicinity of 30 GHz but is broadly applicable to
systems operating between 10 and 66 GHz.

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 IEEE 802.16 -Goals
• Provide wireless high-speed Internet access to home
and business
• subscribers, on metropolitan distances
• BS can handle thousands of subscriber stations (SS)
• Access control prevents collisions
• Supports for : Data, Legacy voice systems, VoIP,
TCP/IP, Appl.
• with different QoS, and different level of guarantees
• Wireless Solution for “Last Mile” (or “First
Mile”) problem

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 802.16 Entities

BS- Base Station

• PHY and MAC are the main layers
• Central role in point-to multipoint (PMP) modes
• Coordination role in resource management
• Connection/gateway point to other networks ( backhaul, core
• IP, Internet)
• Usually out-door installation
SS – Subscriber Station
• Single user SS – fixed station
• Mobile Station - MS
• MSS - Multiple Subscriber Station (playing role of an AP for
• LAN/WLAN)
• may be installed in-door or out-door
RS - Relay station
• Used in Mobile Multihop Relay (MMR

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 Basic 802.16 topologies and basic components

Operation mode/topologies
• Point to multipoint (PMP)/star topology
• Mesh mode/mesh topology
• (New) Mobile Multihop Relay/tree topology
Medium Access Control (MAC)
• allocates uplink (UL) and downlink (DL) bandwidth to SSes as per their
• individual needs
• real time (rt)
• non-real-time (nrt) classes of services
Duplex modes
• Frequency Division Duplex (FDD)
• Time Division Duplex (TDD) modes
• Frequency spectrum:
• 2-11 GHz, 10-66 GHz
• Line of Sight (LOS) and Non LOS
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 Main Standards

802.16 relevant standards

• 802.16 (Dec. 2001)
• Basic 802.16 standard
• Based on Data over Cable Service I/F Specs (DOCSIS)
• 10-66 GHz licensed spectrum, single carrier (SC)
physical (PHY)
• Line-of-sight (LOS),
• Theoretical rates up to 134Mbit/s, real < 70Mbit/s, typical <
12MBit/s
• Fixed technology, point-to-multipoint (PMP) topology
• Coverage – theoretically- 30-mile radius from BS (
real deployments~20Km)
• Now withdrawn

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802.16a (2003)
• 2-11 Ghz - licensed/unlicensed bandwidths
• Channel size ranges: 1.75 – 20 MHz
• PMP and Mesh topologies
• LOS and non-line-of-sigth (NLOS)- applicable to urban areas
• Rates <70MBps, distances up to 30 miles
• Extension:
• Single Carrier (SC)
• 256 point transform Orthogonal Frequency Division
Multiplexing (OFDM)
• 2048 points transform OFDMA (OFD Multiple Access)

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802.16b (5-6 Ghz)
• Now withdrawn
• 802.16c (2002) - detailed system profiles for 10-66 GHz
802.16 standard
• Now withdrawn
802.16d (2004) basic current fixed mode- standard
• Aligned with ETSI HIPERMAN std.
• includes the a/b/c amendments
• Topologies: PMP and mesh,70 Mbps

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• 802.16e (Mobile Wireless MAN), 2005
• Lower data rates of 15 Mbps, full nomadic and mobile
use including
• handover
• enhancements to 802.16-2004
• • better support for QoS
• • Scalable OFDMA
• called “Mobile WiMAX”
• 2.3, 2.5 GHz bands
• Supports devices as : mobile smart phones, PDAs,
Notebooks, Laptops

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802.16f
• Management information base
802.16g
• Management plane procedures and services
802.16h
• Improved coexistence mechanisms for license-
exempt operation
802.16j
• Multi-hop relay specification
802.16k
• 802.16 bridging

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802.16m
• Amendment for advanced air interface looking to the future
• It is anticipated that it will provide data rates of 100 Mbps
for mobile applications and 1 Gbps for fixed applications
• cellular, macro and micro cell coverage, with currently no
restrictions on the RF bandwidth although it is expected to be
20 MHz or more

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 WiMAX

• WiMAX (Worldwide Interoperability for Microwave

Access) is a wireless communications standard designed
to provide 30 to 40 megabit-per-second data rates,
• In 2011 update providing up to 1 Gbit/s for fixed stations.
• The name "WiMAX" was created by the WiMAX
Forum, which was formed in June 2001 to promote
conformity and interoperability of the standard.

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 WiMAX 802.16d and e

• IEEE802.16-2004 include P2P and mesh access networks

• 2-11GHz NLOS 10-66 GHz LOS
• During 2005 IEEE 802.16e includes mobility.
• IEEE802.16 is supported by the industry group WiMAX
• IEEE802.11 is supported by the industry group WiFi

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• 802.16.1 (10-66 GHz, line-of-sight, up to 134Mbit/s)
• 802.16.2 (minimizing interference between
coexisting WMANs)
• 802.16a (2-11 Ghz, Mesh, non-line-of-sight)
• 802.16b (5-6 Ghz)
• 802.16c (detailed system profiles)
• 802.16e (Mobile Wireless MAN)

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 WiMax Internetworking with 3GPP

• The 3rd Generation Partnership Project (3GPP) unites [Six]

telecommunications standard development organizations
known as “Organizational Partners” and provides their
members with a stable environment to produce the highly
successful Reports and Specifications that define 3GPP
technologies.
• The Four Technical Specification Groups (TSG) in 3GPP are
Radio Access Networks (RAN), Service & Systems Aspects
(SA), Core Network & Terminals (CT) and GSM EDGE
Radio Access Networks (GERAN).

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• 3GPP technologies from these groups are constantly
evolving through Generations of commercial cellular /
mobile systems Since the completion of the first LTE and the
Evolved Packet Core specifications, 3GPP has become the
focal point for
mobile systems beyond 3G.

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