..
...
Virtual paired bridge E
Aggregated links
Ethernet Bridging 409
controlled loopback capability for arbitrary data; and the ability to extract byte, packet,
and error statistics from the interface at the other end of the link and to generate error
reports when error thresholds are exceeded. However, IEEE 802.3ah OAM applies only
to single links, not to networks.
IEEE Project P802.1ag Connectivity Fault Management (CFM) is nearing completion
at this writing. IEEE 802.1 has developed this standard in cooperation with the development
in ITU-T Q.5/13 of ITU-T recommendation Y.1731, Ethernet OAM. Y.1731
builds upon P802.1ag and defines a superset of the P802.1ag capabilities. Their provisions
are useful to providers, customers, and intermediate providers who are both.
IEEE P802.1ag provides three operations in the context of a layered environment of
providers and customers. The three operations are
?– Connectivity checking Every endpoint of an EVC (two UNIs for an E-Line
and two or more for an E-LAN) transmits a periodic multicast connectivity check
message (CCM) that contains the identity of the EVC and the transmitting endpoint.
Pages:
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922