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[IPFIX] Mistake in PSAMP RFCs: Selector ID length



Dear all,

We found a mistake in the PSAMP RFCs.

RFC5477

8.1.2. selectorId

Description: The Selector ID is the unique ID identifying a Primitive Selector. Each Primitive Selector must have a unique ID in the Observation Domain. Abstract Data Type: unsigned16 <------------------ Data Type Semantics: identifier ElementId: 302 Status: current


RFC5476, the selectorID length is 4 bytes in ALL examples (and there are many).

   IPFIX Options Template Record:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Set ID = 3           |          Length = 26          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Template ID = 262      |         Field Count = 4       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Scope Field Count =  1    |0|  selectionSequenceId = 301  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |       Scope 1 Length = 4      |0|     ingressInterface = 10   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Field Length = 4       |0|      selectorId = 302       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Field Length = 4       |0|      selectorId = 302       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Field Length = 4       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The proposed solution is to increase the Selector ID length and put an ERRATA on RFC5477.
16 bits is definitely not enough and clearly not was intended. Since we can do reduced length encoding with larger identifiers, we don't see any harm in making all identifiers 64 bit

Feedback?

Regards, Benoit.