Configuring Vjhc On A Ppp Link - Huawei AR530 Series Configuration Manual

Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - WAN
Pre-configuration Tasks
Before configuring PPP compression, complete the following task:
l
Configuration Process
You can configure at least one of VJHC, IPHC, and Stac LZS compression on an interface.
If both VJHC and IPHC are configured on an interface, IPHC takes effect.

2.5.4.1 Configuring VJHC on a PPP Link

Context
Van Jacobson Header Compression (VJHC) complies with RFC 1144 and is an algorithm for
compressing TCP/IP packet headers on Point-to-Point Protocol (PPP) links. The two devices on
a PPP link use IP Control Protocol (IPCP) to negotiate with each other for VJHC capability,
which improves transmission efficiency over PPP links.
A TCP/IP header has 40 bytes, including a 20-byte IP header and a 20-byte TCP header. After
a TCP connection is set up, all TCP/IP packets transmitted over the TCP link contain the IP and
TCP headers. After compressed by VJHC, the TCP/IP header length is reduced from 40 bytes
to only 3 to 5 bytes, and therefore packets can be transmitted faster on the PPP link.
Ensure that the PPP link VJHC function is configured on the peer device; otherwise, the PPP compression
negotiation between the two ends fails.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface interface-type interface-number
The view of a specified interface is displayed.
Step 3 Run:
ip tcp vjcompress
VJHC is configured on the interface.
By default, VJHC is not configured on an interface.
Step 4 Restart the interface.
You can restart an interface by using the following methods:
l Run the shutdown command and then the undo shutdown command.
l Run the restart command.
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Issue 01 (2014-11-30)
Configuring basic PPP functions
NOTE
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