Endpoint X is operationally up if at least one of its objects is operationally up. It is down if all its objects are operationally down.
If the SAP in endpoint X transitions locally to the down state, or receives a SAP down notification by SAP-specific OAM signal, the node must send T-LDP SAP down status bits on the Y endpoint ICB spoke-SDP only.
The Ethernet SAP does not support the SAP OAM protocol. All other SAP types cannot exist on the same endpoint as an ICB spoke-SDP because a non-Ethernet SAP cannot be part of an MC-LAG instance.
If the ICB spoke-SDP in endpoint X transitions locally to the down state, the node must send T-LDP SDP-binding down status bits on this spoke-SDP.
If the ICB spoke-SDP in endpoint X receives T-LDP SDP-binding down status bits or pseudowire not forwarding status bits, 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 X have any of the following happen, the node must send status bits of SAP down over all Y endpoint spoke-SDPs, including the ICB:
transition locally to down state
receive a SAP down notification by remote T-LDP status bits or by SAP-specific OAM signal
receive status bits of SDP-binding down
receive status bits of pseudowire not forwarding
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, receive any of the following, the node saves this status and takes no further action:
T-LDP SAP down status bits
T-LDP SDP-binding down status bits
status bits of pseudowire not forwarding
The saved status is used for selecting the active transmit endpoint object.
If all objects in endpoint Y, except the ICB spoke-SDP, have any of the following happen, the node must send status bits of SDP-binding down over the X endpoint ICB spoke-SDP only:
transition locally to down state
receive T-LDP SAP down status bits
receive T-LDP SDP-binding down status bits
receive status bits of pseudowire not forwarding
If all objects in endpoint Y have any of the following happen, the node must send status bits of the SDP-binding down over the X endpoint ICB spoke-SDP, and must send a SAP down notification on the X endpoint SAP by the SAP-specific OAM signal, if applicable:
transition locally to down state
receive T-LDP SAP down status bits
receive T-LDP SDP-binding down status bits
receive status bits of pseudowire not forwarding
An Ethernet SAP does not support signaling status notifications.