[cisco-voip] +E.164 digit dial plan with non-DID numbers

[Roger Wiklund]

> So let’s say I have a site1 with 40 IP phones. Site1 has 6 POTS lines setup
> in a hunt group with the main number being 3195554000. Each IP phone is
> given an extension in the 1XXX range, example 1001, 1002, 1003 and so on.
> How should I globalize this out to other internal clients and to the PSTN?
>
>
>
> Now lets take site2. This site has 90 IP phones and a block of numbers from
> the PSTN of 31955561XX. Site2 has several internal only DNs such as bells,
> paging numbers, intercom numbers and lobby phones that the customer does not
> want to use DID numbers on. How would I accomplish this and still globalize
> the numbers correct?
>

It sounds like you have already read the 8.x SRND, but search for
Site-Code Based On-Net Form in the document.

IMHO calling/called number globalization makes most sense for PSTN
calls togheter with Local Route Group.

>From the SRND:

Site-Code Based On-Net Form:
In systems where the majority of inter-site calls are dialed by using
an on-net scheme based on site codes, it is better to advertise DNs in
their site-code form, along with a set of rules to allow their
failover to the PSTN.

Each DN is globally reachable within the system by dialing an
inter-site access code, followed by a site code, followed by a local
extension. For example, user Paul in Liverpool can be reached from
anywhere on the enterprise network by dialing inter-site access code
8, followed by site code 555 (Liverpool, England), followed by the
local extension 1234. Combined, these parts yield a global DN of
85551234, which is globally unique within the network.


+E.164 Based On-Net Form:
In systems where the majority of inter-site calls are dialed by using
the PSTN form of DNs, it is better to advertise DNs in their
associated +E.164 form. The +E.164 form carries in it all the
information that allows any user in any system (on-net or off-net) to
reach the destination DN across any network. Cisco recommends that the
DN ranges learned from the SAF CCD service be stored as-is, in their
+E.164 form, and that local user input be globalized to match it.

For example: user Paul in Liverpool uses a phone whose line DN is
defined as 1234 in the Liverpool partition in the English cluster.
However, any coworker in a different site calls Paul by dialing the
locally significant form of Paul's +E.164 form DID (+44 15 4555 1234).
For Wolfgang in Austria, it is 0 00 44 15 4555 1234, and for Elvis in
Memphis, TN, it is 9 011 44 15 4555 1234. User Ringo, calling from a
different site in Liverpool, dials 9 0154 555 1234 to reach Paul. For
user Edge, on the road somewhere in the world, the call to Paul takes
on the form of a click-to-call action from a laptop, to +44 15 4555
1234.

If you have a bunch of phones with internal only extensions there is
really no way of globalizing that number to a E.164 unless you fake
the full number.
However if you have a DID range for your phones then you might gain
from globalizing when it comes to AAR etc.

The designs I've done I have kept on-net calls as is and dialing with
site-codes+extension. I have also configured translation patterns with
+E.164 for force-on-net if they happen to dial it that way.

Globalization comes in to play with PSTN calls togheter with LRG.
Calling/called party transformation done on each gateway to normalize
calling/called number when leaving the gateway to the PSTN

Just my 2 cents.

/Roger