Transition Networks
S4224 Web User Guide
33558 Rev. C
Page 225 of 669
Loop Back State
Transaction ID
The transaction id of the first LBM transmitted. For each LBM transmitted (To Send) the transaction id in
the PDU is incremented.
Transmitted
The total number of LBM PDU transmitted.
Reply MAC
The MAC of the replying MEP/MIP. In case of multi-cast replies can be received from all peer MEP in the
group.
Received
The total number of LBR PDU received from this 'Reply MAC'.
Out Of Order
The number of LBR PDU received from this 'Reply MAC' with incorrect 'Transaction ID'.
Link Trace
Enable
Link Trace based on transmitting/receiving LTM/LTR PDU can be enabled/disabled. Link Trace is
automatically disabled when all 5 transactions are done with 5 sec. interval - waiting 5 sec. for all LTR in
the end. The LTM PDU is always transmitted as Multi-cast Class 2.
Linktrace Messages (LTMs) and Linktrace Replies (LTRs) are used to track the path, hop-by-hop, to a
unicast destination MAC address. At the request of the operator, a local MEP sends an LTM. Each hop
that has a maintenance point sends an LTR back to the originating MEP. This allows the administrator to
discover connectivity data about the path (conceptually similar to IP traceroute).
Priority
The priority to be inserted as PCP bits in TAG (if any).
Peer MEP
This is only used if the 'Unicast MAC' is configured to all zeros. The Link Trace Target MAC will be taken
from the 'Unicast Peer MAC' configuration of this peer.
Unicast MAC
This is only used if NOT configured to all zeros. This will be used as the Link Trace Target MAC. This is
the only way to configure a MIP as Target MAC.
Time To Live
This is the LTM PDU TTL value as described in Y.1731. This value is decremented each time forwarded
by a MIP. Will not be forwarded on reaching zero. The valid LT TTL range is 0-255.