Huawei Quidway NetEngine40E, Configuration Manual - Reliability

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Table 8-12 EFM OAMPDU types and functions
OAMPDU Type Function
Information OAMPDU Used to detect link connectivity. EFM entities in the
handshake stage send information OAMPDUs at a
specific interval to detect link connectivity.
Event notification OAMPDU Used to monitor links. When detecting an errored
symbol event , errored frame event , or errored frame
second event , an interface sends an event notification
OAMPDU to notify the remote device of the event.
Loopback control OAMPDU Used to control the remote device's OAM remote
loopback state. The OAM remote loopback command
value contained in the Loopback Control OAMPDU
Data field of a loopback control OAMPUD determines
whether to enable or disable remote loopback.
EFM Functions
Basic EFM functions are described as follows:
l Remote device discovery
The remote device discovery process is used to establish and maintain EFM connections.
– During the remote device discovery process, an EFM entity discovers remote EFM
entities and establishes sessions with them. Interconnected EFM entities determine
whether to set up EFM connections by exchanging information OAMPDUs that carry
EFM configuration information and supported EFM capabilities.
–
After an EFM connection is established, the EFM entities at both sides exchange
information OAMPDUs at a specified interval (called a handshake message
transmission interval) to check whether the EFM connection is working properly. If an
EFM entity receives no information OAMPDU within the EFM connection timeout
period, the EFM entity considers that the EFM connection is closed.
l Link monitoring
When the physical connection in the network is not closed but network performance is
deteriorating gradually, fault detection on an Ethernet link is difficult. Link monitoring is
used to detect link layer faults in various environments. EFM entities exchange event
notification OAMPDUs to monitor links.
When detecting one of the link events listed in
Table 8-13 , the local EFM entity sends an
event notification OAMPDU to notify the remote EFM entity. This mechanism helps
network administrators to keep track of network status.
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.
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