Alcatel-Lucent 7750 SR OS Service Manual page 142

Pseudowire Redundancy Service Models
If all objects in endpoint "X" transition locally to down state, and/or received a SAP down
notification via remote T-LDP status bits or via SAP specific OAM signal, and/or received status
bits of SDP-binding down, and/or received status bits of pseudowire not forwarding, the node
must send status bits of SAP down over all "Y" endpoint spoke SDPs, including the ICB.
Endpoint "Y" is operationally up if at least one of its objects is operationally up. It is down if all its
objects are operationally down.
If a spoke SDP in endpoint "Y", including the ICB spoke SDP, transitions locally to down state,
the node must send T-LDP SDP-binding down status bits on this spoke SDP.
If a spoke SDP in endpoint "Y", including the ICB spoke SDP, received T-LDP SAP down status
bits, and/or received T-LDP SDP-binding down status bits, and/or received status bits of
pseudowire not forwarding, the node saves this status and takes no further action. The saved status
is used for selecting the active transmit endpoint object.
If all objects in endpoint "Y", except the ICB spoke SDP, transition locally to down state, and/or
received T-LDP SAP down status bits, and/or received T-LDP SDP-binding down status bits, and/
or received status bits of pseudowire not forwarding, the node must send status bits of SDP-
binding down over the "X" endpoint ICB spoke SDP only.
If all objects in endpoint "Y" transition locally to down state, and/or received T-LDP SAP down
status bits, and/or received T-LDP SDP-binding down status bits, and/or received status bits of
pseudowire not forwarding, the node must send status bits of SDP-binding down over the "X"
endpoint ICB spoke SDP, and must send a SAP down notification on the "X" endpoint SAP via the
SAP specific OAM signal if applicable. An Ethernet SAP does not support signaling status
notifications.
Page 142 7750 SR OS Services Guide