Denial of service attacks apparently from UUNET Netblocks

Jay R. Ashworth jra at
Wed Oct 8 02:50:44 UTC 1997

On Tue, Oct 07, 1997 at 06:20:01PM -0700, Dalvenjah FoxFire wrote:
[ David Lesher:]
> > Just want to make sure all parties here do not think ANI == CNID.
> > They are different critters. You get CNID usually. Real time
> > ANI is available on 800 trunks, but at a cost.
> 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?

Sometimes.  CNID bounces around with forwarded calls, as was pointed
out to me in private mail earlier today, whilst ANI will be from the
_last_ site in a forwarding chain -- since that's the only place an
INWATS subscriber is paying for a call from.

> Or does CNID report the number regardless of Caller-ID blocking on PRI
> lines/etc?

No, CNID is Caller-ID.  Blocking is _supposed_ to be implemented by the
_terminating_ end office.  If you receive your traffic over dedicated
trunks from an IXC, rather than a LEC, you're not _supposed_ to get
it... but I'd be unsurprised if some IXC's get this wrong.

I _would_ be surprised if many LEC's were blowing this.

> (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.)

You assume correctly.

-- jra
Jay R. Ashworth                                                jra at
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