Specifications

Appendix C Operation, Administration and Maintenance (OAM) Installation and Operation Manual
C-4 OAM Flows LA-210 Ver. 1.5
Figure C-3. One Flow per UNI
• In case of multiple flows per UNI ( Figure C-4 ), PM and CC are transmitted
three times.
Figure C-4. Multiple Flows per UNI
• In case of one flow and multiple CoS (Service Instances) per UNI ( Figure C-5 ),
the PM is transmitted three times and the CC – once.
Figure C-5. One Flow and Multiple CoS (Service Instances) per UNI
C.4 OAM Flows
Figure C-6 illustrates a typical OAM traffic flow. The OAM message is transmitted
from the source MEP 1 to the destination MEP 2 and the reply is transmitted back
The source is also a destination for messages from the other direction.
The OAM interval is one second, so each NTU transmits one request and one
reply and receive one request and one reply. Total of four messages are
transmitted per second per service instance.
MEP 1 MEP 2
Source Destination
OAM Message
Request
OAM Message
Reply
Figure C-6. OAM Flow
OAM Messages Addressing
The OAM defines two modes of addressing, unicast and multicast. Unicast
addressing is used for point-to-point connections, while multicast addressing is