Allied Telesis AT-S70 - Manual (Page 93)

AT-S70 Management Software User’s Guide
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The OAMPDU types are described below:
ˆ Information OAMPDUs – Information OAMPDUs are used for
discovery; they are variable-length OAMPDUs. There are three TLVs
for Information PDUs: Local Information, Remote Information, and
Organizational Specific. Local and Remote Information is used in the
discovery process. The Organizational Specific Information TLV is
used for vendor extensions.
ˆ Event OAMPDUs – Event OAMPDUs are used for link monitoring,
they are variable-length OAMPDUs. The data field in this event
OAMPDU contains a data field of one or more link event TLVs.
ˆ Loopback Control OAMPDUs – Loopback Control OAMPDUs are
used to provide the loopback command.
ˆ Variable Request/Response OAMPDUs – The Variable Request/
Response OAMPDUs accessible through OAM must be in the
Ethernet branch of the management information based (MIB) tree. For
more information, refer to “MIB Variable Retrieval and Extensions” on
page 93.
ˆ Organizational Specific OAMPDUs – Organizations Specific
OAMPDUs are used to define events that are of variable-length. They
are variable-length OAMPDUs and are distinguish by the Organization
Unique Identifier (OUI).
ˆ Unsupported OAMPDUs – Unknown/unsupported OAMPDUs are
used to send the PDUs to the OAM Client. This is different from typical
Ethernet (802.3x) behavior, which filtered unsupported opcodes.
OAM Remote
Loopback
OAM Remote loopback is used to test the link performance. This remote
loopback is most useful as a diagnostic tool, where it can be used to
identify problem segments in large network. It performs the testing of
segments and links by sending test frames thought the connections. When
in OAM remote loopback mode, the metrics such as delay, throughput, bit
error rate (BER), and jitter can be calculated to determine the overall
quality of a connection.
MIB Variable
Retrieval and
Extensions
The IEEE 802.3ah Ethernet OAM specs define a generic mechanism for
one OAM entity to query another entity for the value of any MIB variable.
MIB variables include all performance and error statistics maintained on
an Ethernet link. This capability provides a generic monitoring capability
for one station to monitor any parameter on another station for
performance or error detection.
The MIB Variable Extensions can be used to implement extra events such
as including additional information during discovery or even adding a
completely proprietary OAM protocol to the standard operation.