Dalvenjah FoxFire sez:
> Just want to make sure all parties here do not think ANI == CNID.
I realize this is probably something one learns in Telco 101, which I
haven't taken, but if CNID == Caller ID, wouldn't ANI be *more* useful?
They came up from different requirements; using different
approaches.
Or does CNID report the number regardless of Caller-ID blocking on PRI
lines/etc?(I'm assuming that CNID == standard Caller-ID as it appears on POTS, and
that ANI == the special service that 800-lines get that *always* reports
the number, regardless of blocking..if I'm wrong, I'll accept the LART.)
ANI is a BILLING number. Call an 500/800/900# line & that is what
they see. Ex: All 5280 lines at Engulf and Devour will report
the main billing number of 666-7836.
CNID is the calling number. {IN THEORY} even in a large system
[university] the calling number /"extension" appears. But... often
times there are PBX's with outgoing-only trunks {Why? a history of
crude signaling schemes, mostly...} that even if they do ring in;
they end up somewhere else than you intended...
ANI is not blockable. CNID is. The block can be ignored by the
final switch, however, if you are "privileged" enough. And if you
want to spend the $$ [i.e. Fort Meade..] you get dedicated outgoing
trunks that don't pass SS7 at all.