Background: Know: MIB tables , Prerequisites - demultiplexing identifiers, Ethertype, IP protocol, port number, PDU, segmentation and reassembly, header decoding, Recognize:
RMON2 protocolDir Protocol Directory
The RMON2 Protocol Directory Group (protocolDir) is defined on page 20 of RFC 4502. It presents a master directory of protocol types the probe is capable of monitoring and allows the addition, deletion, and configuration of protocol types in this list. 
The protocolDirID and protocolDirParameters are used as indexes that uniquely identify the protocolDirEntry in protocolDirTable, in which the protocols that this agent has the capability to decode and count are listed. The protocols are identified by a list of demultiplexing (i.e., the reverse of multiplexing) identifiers that lead to the protocols, e.g., Ethertype, IP Protocol, Transport layer port number. See RFC 2895  for more ProtocolDirTable index examples.
See also Edit
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