Scribd
Upload
33 views13 pages

NAT and PAT

The document discusses Network Address Translation (NAT) and Port Address Translation (PAT), detailing their types, features, benefits, and drawbacks. NAT allows for the mapping of private IP addresses to public ones, while PAT enables multiple devices to share a single public IP by using unique port numbers. The document also highlights the advantages of NAT and PAT in terms of network efficiency and security, as well as the limitations of NAT that PAT addresses.

Uploaded by

xihuatl074
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
33 views13 pages

NAT and PAT

The document discusses Network Address Translation (NAT) and Port Address Translation (PAT), detailing their types, features, benefits, and drawbacks. NAT allows for the mapping of private IP addresses to public ones, while PAT enables multiple devices to share a single public IP by using unique port numbers. The document also highlights the advantages of NAT and PAT in terms of network efficiency and security, as well as the limitations of NAT that PAT addresses.

Uploaded by

xihuatl074
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 13

NAT and PAT

Content

 Network Address Translation


– Static and Dynamic
 Port Address Translation
 Configuration and testing
 Issues with NAT/PAT

2 19 June, 2022
Private Addressing

3 19 June, 2022
NAT

 A NAT-enabled device typically operates at


the border of a stub network.

4 19 June, 2022
NAT Terms

 Inside Local Addresses – An IP address assigned to a host


inside a network. This address is likely to be a RFC 1918
private address.
 Inside Global Address – A legitimate IP address assigned
by the NIC or service provider that represents one or
more inside local IP address to the outside world.
 Outside Local Address - The IP address of an outside host
as it known to the hosts in the inside network.
 Outside Global Address - The IP address assigned to a host
on the outside network. The owner of the host assigns
this address.
5 19 June, 2022
NAT Features
 Static NAT is designed to allow one-to-one mapping of local
and global addresses.
 Dynamic NAT is designed to map a private IP address to a
public address.

6 19 June, 2022
Static NAT

 For 1 local ip, one global ip is fixed.


 It is not possible to give service to all host.

7 19 June, 2022
PAT Features

 PAT uses unique source port numbers on the inside global


IP address to distinguish between translations.

8 19 June, 2022
NAT Benefits

 Eliminates re-assigning each host a new IP


address when changing to a new ISP
 Eliminates the need to re-address all hosts
that require external access, saving time and
money
 Conserves addresses through application
port-level multiplexing
 Protects network security
9 19 June, 2022
NAT Benefits

 Increases the flexibility of connections to the


public network
 Provides consistency for internal network
addressing schemes.

10 19 June, 2022
NAT Drawbacks

 Performance is degraded
 End-to-end functionality is degraded
 End-to-end IP traceability is lost
 At a time, a fixed number of user can use
global ip.
 Processing time is increased cz extra
translation is required

11 19 June, 2022
Why PAT over NAT

 PAT is used to overcome the drawbacks of NAT.


 Suppose we have only 10 public ip but 200 host.
When 10 users are using 10 public ip by NAT then if
other host comes then they have to wait.
 Using PAT this is resolved. One public ip can be
used by many hosts, only changing the port address.
 Using one global ip PAT can give service to around
1000 local ip.

12
Tutorial

NAT explained:
 https://www.youtube.com/watch?v=FTUV0t6JaDA

PAT Explained:
 https://www.youtube.com/watch?v=BZDXzsIcrlc

13 19 June, 2022

You might also like