Raisecom
ISCOM2600G-HI (A) Series Configuration Guide
9 OAM
Raisecom Proprietary and Confidential
Copyright © Raisecom Technology Co., Ltd.
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Service Vlan ID: 3
Customer Vlan ID: 0
MD Level: 3
Remote DEST MAC: 000e.5e00.0001
Transmit Interval(msec): 1000
Frame Number: 5
Pdu Size(octets): 64
Avail Flr Threshold(0.001%): 50000
Avail Consec interval: 10
Avail consecutive high flr: 5
Schedule Life(sec): 20
Schedule Period(sec): ----
Schedule Status: Initial
9.5 BFD
9.5.1 Introduction
Bidirectional Forwarding Detection (BFD) is used to detect connectivity of data protocol
between systems or in the same path. The can be a physical link, logical link, or channel.
When finding a communication fault between systems, BFD notifies applications at the upper
layer.
Detection mechanism
BFD establishes a session between two endpoints in the communication system, and
periodically sends BFD control packets in the detection path. If one endpoint fails to receive
BFD control packets within the required time, BFD considers that fault occurs in the path.
BFD control packets are encapsulated in the UDP packets and then are transmitted. At the
initial stage of the session, both systems negotiate through parameters carried on the control
packets (such as session identifiers of two endpoints, the minimum interval for receiving and
sending packets, BFD session status of the local endpoint). When the negotiation is successful,
both systems send BFD control packets according to negotiated time of receiving and sending
packets.
Modes for establishing BFD sessions
There are two modes for establishing BFD sessions: statically establishing BFD sessions and
dynamically establishing BFD sessions. BFD distinguishes these two session modes through
identifiers of the local endpoint and remote endpoint in the control packet.
Statically establishing BFD session: configure BFD session parameters manually,
including identifiers of local and remote endpoints.
Dynamically establishing BFD session: the system automatically assigns values within
dynamic session identifier area to be those of the local BFD session, and the local and
remote endpoints will negotiate. After receiving negotiated packets, the remote endpoint
determines whether identifiers match the local BFD session. If yes, the remote endpoint
automatically learns identifiers of the remote session.
The ISCOM2600G-HI series switch supports statically establishing BFD sessions.