R2511-HP MSR Router Series Layer 2 - WAN Command Reference(V5)

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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.
Usage guidelines
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 virtual circuit). 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 except the final fragment. After receiving
these fragments, the DTE at receiving end will reassemble them to a datagram and submit it to the
upper-layer protocol based on the M bit. Consult access ISP about this maximum receiving packet length.
The maximum receiving packet length is equivalent to the maximum sending packet. Do not configure
these two parameters with different values unless the access ISP allows.
Examples
# Set the maximum receiving packet length and maximum sending packet length on X.25 interface Serial
2/0 to 256 bytes.
<Sysname> system-view
[Sysname] interface serial 2/0