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Two way DMM packet receiving is enabled.
----End
5.4.5 Enabling the Two-way Frame Delay Measurement in a VLAN
The two-way frame delay measurement in a VLAN can work normally only after you enable
the two-way frame delay measurement in the VLAN.
Context
To implement the two-way frame delay measurement, you need to specify the remote MEP ID
or the destination MAC address, the interval for sending DMM frames, and the number of DMM
frames sent each time.
l
If the local MEP has not learnt the MAC address of the remote MEP, you must specify the
destination MAC address for the two-way frame delay measurement.
l
If the local MEP has learnt the MAC address of the remote MEP, you can specify the remote
MEP ID for the two-way frame delay measurement.
The two-way frame delay measurement is performed on end-to-end MEPs. A MEP receives a
DMM frame and returns a DMR frame to carry out the two-way frame delay measurement. After
the two-way frame delay measurement is configured, a MEP periodically sends DMM frames
with the TxTimeStampf value (timestamp at the time of sending the DMM frame). After
receiving the DMM frame, the remote MEP adds the RxTimeStampf value (timestamp at the
time of receiving the DMM frame) to the DMM frame, generates a DMR frame with the
TxTimeStampb value (timestamp at the time of sending the DMR frame), and sends the message
to the requesting MEP. Every field in the DMM frame is copied to the DMR frame except that
the source and destination MAC addresses are swapped and the message type is changed from
DMM to DMR. Upon receiving the DMR frame, the requesting MEP calculates the two-way
frame delay based on the following formula:
Two-way frame delay = (RxTimeb - TxTimeStampf) - (TxTimeStampb - RxTimeStampf)
Do as follows on the devices configured with MEPs on two ends of the link:
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
cfm md
md-name
The MD view is displayed.
Step 3
Run:
ma
ma-name
The MA view is displayed.
Step 4
Run:
delay-measure two-way
{
mac
mac-address
|
remote-mep mep-id
mep-id
}
interval
interval-value
count
count-value
Quidway S3700 Series Ethernet Switches
Configuration Guide - Reliability
5 ITU-T Recommendation Y.1731 Configuration
Issue 01 (2011-10-26)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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