Command Reference Guide

3Com Router 5000 Family and Router 6000 Family x25 packet-size ● 333
Command Reference
x25 packet-size
Purpose Use the x25 packet-size command to set the maximum input and output packet
lengths of X.25 interface.
Use the undo x25 packet-size command to restore their default values.
Syntax x25 packet-size input-packet output-packet
undo packet-size
Parameters input-packet
Maximum input packet length (in bytes). Valid values
are 16 (inclusive) to 4096 (inclusive) and must be the
integer power of 2. By default, the maximum input
packet length of X.25 interface is 128 bytes.
output-packet
Maximum output packet length (in bytes). Valid values
are 16 (inclusive) to 4096 (inclusive) and must be the
integer power of 2. By default, the maximum output
packet length of X.25 interface is 128 bytes.
Example Set the maximum receiving packet length and maximum sending packet length on
X.25 interface Serial0/0/0 to 256 bytes.
[3Com-Serial0/0/0] x25 packet-size 256 256
View This command can be used in the following views:
■ Interface view
Description Usually, the X.25 packet-switching network has a limitation of the transmission
packet size, and the maximum size of a data packet sent by the DTE shall not exceed
this size (otherwise it will trigger the reset of the VC).In this way, the DTE devices at
sending end and receiving end are required to have datagram fragmentation and
reassembly functions. The DTE device at sending end fragments the datagram with a
length exceeding the maximum transmission packet length based on the maximum
transmission packet length, and sets M bit in other fragments besides the final
fragment. After receiving these fragments, the DTE at receiving end will reassemble
them as a datagram to submit the upper-layer protocol based on the M bit. Please
consult users’ ISP about this maximum receiving packet length.
Normally, the maximum receiving packet length is equivalent to the maximum send
packet. Unless users’ ISP allows, please do not set these two parameters to different
values.
Related Commands ■ x25 call-facility
■ x25 pvc