Cisco ASR 920 series Configuration Guide Ethernet Router

control-word command by default, enable the command to get the DMM time stamp working. Cisco
ASR 9000 Series Routers and ALU 7450 are examples of peer platforms where the control-word
command needs to be enabled.
•
When the core network has multiple paths, the Tx and Rx DMM/DMR packets can be sent and received
on different ports. If the ports belong to a different interface module (IM), time stamping can be out of
sync and in certain cases the Rx value can be lower than the Tx value. This value will be displayed as
0 in the raw database output. As a workaround, configure Precision Time Protocol (PTP) between the
two connectivity fault management (CFM) endpoint routers.
•
Y1731 is supported with the rewrite command configuration on Ethernet Flow Points (EFPs) throughout
the Layer 2 circuit. However, the configuration may be in such a way that the Y1731 PDUs may be
transmitted without a tag. This results in the other end of the Layer 2 circuit not being able to ascertain
the CoS value which determines the SLA session to which the PDUs belong. Therefore, the rewrite
command configuration is not supported
•
Y.1731 Performance Monitoring (PM) is not supported on MEPs that are configured on TEFP.
•
Y.1731 Performance Monitoring (PM) is not supported on MEPs that are configured on ports.
In ITU-T Y1731, 1DM measurement should mandate only PTP to have clock sync between sender &
receiver.
Note
Information About ITU-T Y.1731 Performance Monitoring in a
Service Provider Network
Frame Delay and Frame-Delay Variation
The Frame Delay parameter can be used for on-demand OAM measurements of frame delay and frame-delay
variation. When a maintenance end point (MEP) is enabled to generate frames with frame-delay measurement
(ETH-DM) information, it periodically sends frames with ETH-DM information to its peer MEP in the same
maintenance entity. Peer MEPs perform frame-delay and frame-delay variation measurements through this
periodic exchange during the diagnostic interval.
An MEP requires the following specific configuration information to support ETH-DM:
• MEG level—MEG level at which the MEP exists
•
Priority
• Drop eligibility—marked drop ineligible
•
Transmission rate
•
Total interval of ETH-DM
•
MEF10 frame-delay variation algorithm
Carrier Ethernet Configuration Guide (Cisco ASR 920 Series)
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ITU-T Y.1731 Performance Monitoring in a Service Provider Network
Information About ITU-T Y.1731 Performance Monitoring in a Service Provider Network

Cisco ASR 920 series Specifications

General

Brand	Cisco
Model	ASR 920 series
Category	Network Router
Language	English