Avaya P332GT-ML, Руководство по установке и настройке

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Chapter 12 Avaya P330 Layer 3 Features
116 Avaya P332GT -ML User’s Guide
IP Fragmentation and Reassembly
IP Fragmentation and Reassembly Overview
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
IP Fragmentation/Reassembly CLI Commands
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