tree 1733da5c7aa548205dc827f99a3707796f6e2bf7
parent 5336f57f05cde9e83b4a671a78d61ffdfc8ce5a6
author Neels Hofmeyr <neels@hofmeyr.de> 1535466051 +0200
committer Neels Hofmeyr <neels@hofmeyr.de> 1536009143 +0200

generate shorter 'I:' conn IDs

Reduce the number of hex chars generated as Connection Identifier from 32 to 8.

According to RFC3435 2.1.3.2 "Names of Connections", the maximum length is
indeed 32 characters, but there isn't really a benefit of using IDs of that
size. That, and:

A specific SCCPlite MSC is seen to be able to store conn IDs of up to 8 hex
characters of length. If given more than that, it will later send 'ffffffff' as
ID, e.g. in the DLCX message, causing mismatches and rejected DLCX.

Conn IDs need to be unique only within the context of one endpoint, so
producing 32 characters of ID is far beyond overkill, especially if we
currently expect exactly two IDs per endpoint.

Notice that the maximum length of conn ID that can be handled by the message
parsing and composition doesn't change, only the length that an osmo-mgw will
generate upon CRCX does.

Related: OS#3507
Change-Id: Ia290c22a91fca0e5aa44515fca6df00064aff100