X25 Packet-Size - HP MSR series Command Reference Manual

Parameters
8: Uses modulo 8 mode.
128: Uses modulo 128 mode.
Usage guidelines
The slip window is the basis for X.25 traffic control, and the key about the slip window is that the sent
packets are numbered cyclically in order and are to be acknowledged by the peer end. The order in
numbering refers to the ascending order, like "...2, 3, 4, 5, 6...." "Cyclically" means that the numbering
starts again from the beginning when a certain number (called "modulo") is reached. For example,
when the modulo is 8, the numbering goes "...4, 5, 6, 7, 0, 1...."
X.25 defines the following numbering modulos: 8 (also called "basic numbering") and 128 (also called
"extended numbering").
The packet numbering mode on the pair of DTE and DCE must be the same.
Use the shutdown and undo shutdown commands on the interface to apply the new configuration.
The packet numbering mode of X.25 Layer 3 is different from the frame numbering mode of LAPB (Layer
2 in X.25). When modulo 128 is applied to the DTE/DCE interface with high throughput, it improves only
the efficiency of local DTE/DCE interface (point-to-point efficiency) for LAPB. For Layer 3 in X.25, it
improves the efficiency of the two communicating DTE peers (or peer-to-peer efficiency).
Examples
# Set the modulo on the X.25 interface Serial 2/0 to 128.
<Sysname> system-view
[Sysname] interface serial 2/0
[Sysname-Serial2/0] x25 modulo 128

x25 packet-size

Use x25 packet-size to set the maximum input and output packet lengths of X.25 interface.
Use undo x25 packet-size to restore their default values.
Syntax
x25 packet-size input-packet output-packet
undo x25 packet-size
Default
The maximum input packet length is 128 bytes, and the maximum output packet length is 128 bytes.
Views
Interface view
Default command level
2: System level
Parameters
input-packet: Maximum input packet length in bytes. Its value is in the range of 16 (inclusive) to 4096
(inclusive) and must be the integer power of 2.
output-packet: Maximum output packet length in bytes. Its value is in the range of 16 (inclusive) to 4096
(inclusive) and must be the integer power of 2.
362