Avaya P332G-ML Manual Do Utilizador

Chapter 12

Avaya P330 Layer 3 Features

116

Avaya P332G-ML User’s Guide

IP Fragmentation and Reassembly

The P330 supports IP Fragmentation and Reassembly. This feature allows the router 
to send and receive large IP packets where the underlying data link protocol 
constrains MTU (maximum transport unit).
IP fragmentation involves breaking a datagram into a number of pieces that can be 
reassembled later. The IP source, destination, identification, total length, and 
fragment offset fields, along with the "more" fragment and "don't" fragment flags in 
the IP header, are used for IP fragmentation and reassembly. 
IP Fragmentation works as follows: 
•

IP packet is divided into fragments  

•

each fragment becomes its own IP packet 

•

each packet has same identifier, source, destination address 

•

fragments are usually not reassembled until final destination 

In order to...

Use the following command...

Clear the fragment database and 
restore its defaults

clear fragment

Set the maximum number of 
fragments that can comprise a 
single IP packet 

fragment chain

Set the maximum number of 
fragmented IP packets, destined for 
the router, to reassemble at any 
given time

fragment size

Set the maximum number of 
seconds to reassemble a 
fragmented IP packet destined for 
the router.

fragment timeout

Display information regarding 
fragmented IP packets that are 
destined for the router

show fragment