Subject: RE: ENUM Privacy (was RE: [Enum] User ENUM vs Operator ENUM)

From: "Stastny Richard" <[email-masked]>
Date: Tue, 29 Jun 2004 13:15:04 -0400

Jim Reid wrote:

> These trees won't need any opt-in principle as they could be
> used for all numbers served by the operator, including unlisted ones.

[Richard>] So I can reach unlisted numbers only from within the same 
operator?

Richard

_______________________________________________
enum mailing list
enum at ietf.org
https://www1.ietf.org/mailman/listinfo/enum

---

From: Jim Reid <[email-masked]>
Date: Tue, 29 Jun 2004 13:35:52 -0400

>>>>> "richard" == Stastny Richard <Richard.Stastny at oefeg.at> writes:

    >> used for all numbers served by the operator, including unlisted

    richard> So I can reach unlisted numbers only from
    richard> within the same operator?

Depends on the operator, what they choose to make available to
other operators and how it's made available. 

Suppose +10123456789 is an unlisted number living in a block belonging
to TelcoA. TelcoB is in Austria. They have a private ENUM tree that
points all +1 numbers at a SIP server in TelcoC's net in the
USA. TelcoC knows that block 0123456 belongs to TelcoA. TelcoC's
private tree points calls begining with this prefix at a SIP server in
TelcoA's network which can then terminate the call by making the phone
on +10123456789 ring. There's lots of hand-waving going on here, but
you get the general idea. And of course if there's a shared operator
ENUM tree, routing the call gets a whole lot simpler.

---

From: Mike Hammer <[email-masked]>
Date: Tue, 29 Jun 2004 14:45:41 -0400

USA.

TelcoC knows that block 0123456 belongs to TelcoA. TelcoC's
private tree points calls begining with this prefix at a SIP server in
TelcoA's network which can then terminate the call by making the phone
on +10123456789 ring.
Hmmm... TelcoC is in competition with TelcoA and decides to add a 10 second 
delay to call setup messages going to TelcoA (or put them in lower priority 
queue)...  Meanwhile TV add by TelcoC touts how quickly they can setup 
calls compared to their competitors...

Generally, I would suspect that anytime there is more than an originating 
and terminating session-setup "telco", then ENUM is suboptimal.  (Optimal 
could be zero telcos, but security, privacy, mobility and other concerns 
suggest that at least one telco per endpoint is likely.)

Mike
There's lots of hand-waving going on here, but