CANOGA PERKINS 9145EMP NID Software Version 4.0 User Manual
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Service OAM
9145EMP NID Software User’s Manual
Service OAM
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Untagged MEPs on the physical ports, described above (designated in dark blue in Fig-
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Down C-Tagged MEPs on the User port: These MEPs can be used to monitor the C-
VLAN connections between the CPE and the 9145EMP.
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Up C-Tag MEPs on the user port (facing the VLAN multiplexing point): These MEPs are
used to monitor C-VLAN connectivity from the 9145EMP towards the network core. If the
MEP belongs to a Service Multiplexing record with T-Tagging enabled, frames sent by
those MEPs to the network port are triple tagged.
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For the 9145EMP, the SOAM frames initiated by those MEPs are immediately encapsu-
lated in the S-VLAN tag corresponding to the MEP's C-Tag, as per VLAN multiplexing
records. Hence, the SOAM frames are not visible inside the Provider network (unless the
network is able to inspect double tagged, that is, S-C tagged, SOAM frames); only the far-
end demultiplexing point is able to process those frames.
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Up T-Tagged MEPs on the user port. This MEP (maximum one per Service Multiplexing
record) sends double tagged frames on the network port.
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Up S-Tagged MEPs on the user port: These MEPs are monitoring the S-VLAN aggrega-
tion, which originates in the 9145EMP. The frames are single tagged (with a single S-Tag)
when sent on the Network port.
Logically, the up S-Tag MEPs are attached to the virtual C-S connector port, which is a
proxy on the S component, for the User port. Hence, the SOAM frames issued by those
MEPs have the MAC address of the corresponding User port. Interface Status TLV for
the CCM frames issued by those MEPs carry the operational state of the User port. The
corresponding User port (for an S-Tagged MEP) is determined based on the VLAN
multiplexing record configuration.
The T-Tunnel is a boundary point, and not an intermediate point for the SOAM domain.
Hence, there is no need for another MIP positioning on the NID. C-Tagged MIPs continue
to be supported on the User Port. However, if a MIP belongs to a Service Multiplexing
record which has T-Tunneling enabled, then the frames for this MIP are:
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C-Tagged when received/sent on the user port
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Triple tagged (S-T-C) when received or sent on the network port
For example, if an LTM is received for such MIP on the user port, it is C-Tagged. The LTR
sent back by the MIP on the user port is also C-Tagged. The LTM which is being
forwarded by the MIP is triple tagged.