13
ppp compression iphc enable
[
nonstandard
]
By default, IP header compression is disabled.
The
nonstandard
option must be specified when the device communicates with a non-H3C
device.
When the
nonstandard
keyword is specified, only RTP header compression is supported
and TCP header compression is not supported.
4.
Set the maximum number of connections for which an interface can perform RTP header
compression.
ppp compression iphc rtp-connections number
The default setting is 16.
5.
Set the maximum number of connections for which an interface can perform TCP header
compression.
ppp compression iphc tcp-connections number
The default setting is 16.
Enabling PPP link quality monitoring
About PPP link quality monitoring
PPP link quality monitoring (LQM) monitors the quality (packet loss ratio and packet error ratio) of
PPP links (including those in MP bundles) in real time.
If PPP LQM is not enabled, each end of a PPP link periodically sends keepalives to its peer. If PPP
LQM is enabled, Link Quality Reports (LQRs) packets replace keepalives to monitor the link.
The system uses received LQR packets to measure the link quality. If two consecutive measured
results are below the
close-percentage
, the system shuts down the link. Then the system
measures the link quality at an interval that is ten times the LQR interval. If three consecutive
measured results are higher than the PPP LQM
resume-percentage
, the system brings up the
link.
Restrictions and guidelines
A shut-down link must experience a minimum of 30 keepalive intervals before it can come up again.
As a best practice, do not set the keepalive interval to a large value.
If you enable PPP LQM on both sides of a PPP link, make sure both sides have the same PPP LQM
settings. Typically, there is no need to enable PPP LQM on both sides of a PPP link.
As a best practice, do not enable PPP LQM on a DDR dial-up link because DDR tears the link down
when the link is closed by LQM. Then LQM cannot send LQR packets to resume the link.
The configuration of this feature does not affect existing users.
Procedure
1.
Enter system view.
system-view
2.
Enter interface view.
interface interface-type interface-number
3.
Enable PPP LQM.
ppp lqm close-percentage close-percentage
[
resume-percentage
resume-percentage
]
By default, PPP LQM is disabled.
4.
Configure the interface to periodically send LCP echo packets when LQM detects a low quality
link.
