Alcatel-Lucent 7210 SAS M Service Guide

Virtual Leased Line Services
7210 SAS M Services Guide Page 159
Figure 29: Access Node Resilience
In this application, a new pseudowire status bit of active or standby indicates the status of the SAP
in the MC-LAG instance in the SR-Series aggregation node. All spoke SDPs are of secondary type
and there is no use of a primary pseudowire type in this mode of operation. Node A is in the active
state according to its local MC-LAG instance and thus advertises active status notification
messages to both its peer pseudowire nodes, for example, nodes C and D. Node D performs the
same operation. Node B is in the standby state according to the status of the SAP in its local MC-
LAG instance and thus advertises standby status notification messages to both nodes C and D.
Node C performs the same operation.
The 7210 SAS node selects a pseudowire as the active path for forwarding packets when both the
local pseudowire status and the received remote pseudowire status indicate active status. However,
7210 SAS device in standby status according to the SAP in its local MC-LAG instance is capable
Aggregation
node
A
Aggregation
node
C
72107210
Aggregation
node
B
Aggregation
node
D
Inter-chassis
PW for VLL
Active
Active
Active
Active
Standby
Standby
Standby
Standby
Standby
TLDP
Standby Active
Active
Inter-chassis
PW for VLL
Aggregation
node
A
Aggregation
node
C
72107210
Aggregation
node
B
Aggregation
node
D
Inter-chassis
PW for VLL
Active
Standby
Standby
TLDP
Active
Inter-chassis
PW for VLL

Alcatel-Lucent 7210 SAS M Specifications

General

Brand	Alcatel-Lucent
Model	7210 SAS M
Category	Switch
Language	English