Path: utzoo!attcan!uunet!wuarchive!zaphod.mps.ohio-state.edu!casbah.acns.nwu.edu!accuvax.nwu.edu!nucsrl!telecom-request
From: wright@ais.org (Carl Wright)
Newsgroups: comp.dcom.telecom
Subject: Re: New Roaming System for A Carriers
Message-ID: <15996@accuvax.nwu.edu>
Date: 11 Jan 91 05:09:41 GMT
Sender: news@accuvax.nwu.edu
Organization: UMCC, Ann Arbor, MI
Lines: 56
Approved: Telecom@eecs.nwu.edu
X-Submissions-To: telecom@eecs.nwu.edu
X-Administrivia-To: telecom-request@eecs.nwu.edu
X-Telecom-Digest: Volume 11, Issue 27, Message 6 of 7


In article <15879@accuvax.nwu.edu> forrette@cory.berkeley.edu (Steve
Forrette) writes:

>There seems to be a new roaming system that some of the A carriers are
>using (is this perhaps "Roam Across America" or something similar?).
>When you are outside of your local area and registered in another,
>your callers will get a recording telling them what city you are in,
>the roamer port number there, and instructions on how to use it.  This
>is a vast improvement over what we had before (nothing), but still not
>as neat as the call just going through by itself.  Based on my
>experience and a call to Cellular One, here are some details:

> - Registration is automatic - all you have to do is place or receive
>a call in a foreign system in order to activate it.

For many users, the "Registration" process for the phone occurs when
the phone is turned on. By "Registration" I don't intend to say that
your home switch knows your location when you turn the phone on in
another carrier's service area. That probably only happens when your
home switch is requested to verify your credit worthiness by the
switch you are visiting via the roamer validation service company.

In Los Angeles, with Cellular One, you are using one of Ericsson's
most sophisticated installations. They have four AXE-10 switches
networked together so that whenever you turn on your phone, your home
switch (the one you were activated in by Cellular One) knows where you
are at.  They need the information to seamlessly route calls coming in
to you.

The call traffic in Los Angeles has become so intense in some
neghborhoods that PacTel has raised the rates for using your phone in
that area. If you travel through, part of the call is at normal (high)
rates and the part in this neighborhood is charged at still hgher
rates. I forget the neighborhood. Is it Rodeo Drive?

> - The foreign system doesn't need any special equipment.  All they
>need is to be part of the Positive Roamer Verification (PRV) network.
>When your home system gets a MIN/ESN verification request from another
>system (which happens upon your first call), it knows where you are.

This validation actually occurs after the first call is completed.
This is primarily a system to limit roamer fraud. This is provided by
GTETS and APPEX/EDS for almost all cellular carriers. They have even
set up a gateway between them to pass information so that they serve
each others customer base.

The information passed between carrier switches is being increased to
permit the visited switch to know your characteristics as a user and
to treat you like your home system does. It is part of the goal of
providing seamless service.


Carl Wright                     | Lynn-Arthur Associates, Inc.
Internet: wright@ais.org        | 2350 Green Rd., #160
Voice: 1 313 995 5590 EST       | Ann Arbor, MI 48105