>     From fsc-0057:

Ah, perhaps THIS is the source of the problem. EMSI's FSC document number
is "0056". FSC-0057 deals with Areafix, etc.

 > The calling system must list supported protocols first and descending
 > order of preference (the most desirable protocol should be listed
 > first). The answering system should only present one protocol and it
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 > should be the first item in the compatibility_codes field.
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 > The above section requires clarification.

Yes, an "IN" is missing in the first sentence.

 >     Possible mis-interpretations:

 >     Example:
 >     Caller presents:        HYD,ZAP,SLK,ZMO (preference order)
 >     Answerer supports:      SLK,ZAP,ZMO     (preference order)

"SLK,ZAP,ZMO" looks like more than one protocol to me.

 > 1 - the answering system must present the first protocol
 > from the compatibility list of the sender.

What?

 >         (Nonsensical-driven protocol selection)
 >             Answerer presents HYD :)
 >             Session fails since answerer does not support
 > Hydra

Is the "answerer" talking to itself in the above scenario?

 >     3 - the answering system selects it's preferred protocol
 >         from the compatibility list of the sender, regardless
 > of the
 >         sender's positionally indicated preference.

Then that's a software "problem" (receiver side).

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