HP A5830 series Configuration Manual page 22

Maintenance point
An MP is configured on a port and belongs to an MA. MPs fall into two types: MEPs and MIPs.
MEP
•
Each MEP is identified by an integer called a "MEP ID." The MEPs of an MD define the range and
boundary of the MD. The MA and MD to which a MEP belongs define the VLAN attribute and level of
the packets sent by the MEP. MEPs fall into inward-facing MEPs and outward-facing MEPs.
The level of a MEP determines the levels of packets that the MEP can process. The packets transmitted
from a MEP carry the level of the MEP. A MEP forwards packets at a higher level and processes packet
of its level or lower. The processing procedure is specific to packets in the same VLAN. Packets of
different VLANs are independent.
The direction of a MEP (outward-facing or inward-facing) determines the position of the MD relative to
the port.
Figure 4 Outward-facing MEP
As shown in
Figure 5 Inward-facing MEP
Bridge
Port
As shown in
packets to other ports on the device.
MIP
•
A MIP is internal to an MD. It cannot send CFD packets actively. However, it can handle and respond to
CFD packets. The MA and MD to which a MIP belongs define the VLAN attribute and level of the
packets received.
By cooperating with MEPs, a MIP can perform a function similar to ping and traceroute. Like a MEP, a
MIP forwards packets at a higher level without any processing, and only processes packets of its level or
lower.
4, an outward-facing MEP sends packets to its host port.
Figure
Maintenance Association
Bridge
Relay
Entity
5, an inward-facing MEP does not send packets to its host port. Rather, it sends
Figure
Bridge
Bridge
Relay
Entity
Port
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