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Configuring Single-ended SLM in VLL Networking
This section describes how to configure single-ended synthetic loss measurement (SLM) in
virtual leased line (VLL) networking. To collect performance statistics for frame loss on point-
to-multipoint or multipoint-to-multipoint links, deploy single-ended SLM, which helps monitor
link quality.
Context
In VLL networking, single-ended SLM includes on-demand and proactive SLM functions.
On-demand SLM collects single-ended frame loss statistics at one or more specific times for
diagnosis. It is used on the pseudo wire (PW) or attachment circuit (AC) side.
Proactive SLM collects single-ended frame loss statistics periodically. It is used on the PW side
only.
On a network, each packet carries the IEEE 802.1p field, indicating its priority. According to
packet priority, different QoS policies will be applied. On the network shown in
the PE1-to-PE3 traffic has two priorities: 1 and 2, as indicated by the IEEE 802.1p field.
When implementing single-ended SLM for traffic over the PE1-PE3 link, PE1 sends SLM
frames with varied priorities and checks the frame loss. Based on the check result, the network
administrator can adjust the QoS policy for the link.
To collect accurate performance statistics, configure 802.1p priority-based single-ended SLM.
Figure 8-51
Single-ended SLM based on different 802.1p priorities
CE1
PE1
User
Network
User
Network
MEP
Y.1731
Y.1731
User
Network
PE2
PE3
CE3
CE2
VLL
Priority 1
Priority 2
Procedure
l
Configure single-ended on-demand SLM.
–
Configure single-ended on-demand SLM on the PW side.
1.
Perform the following steps on the devices at both ends of a PW where single-
ended on-demand SLM will be implemented:
a.
Run:
system-view
The system view is displayed.
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
8 Ethernet OAM Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
749