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From: grw@cabernet.Eng.Sun.COM (Gregory Whitehead)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Mobile TCP/IP (was Re: Can subnets be separated by another net?)
Message-ID: <139016@sun.Eng.Sun.COM>
Date: 17 Jul 90 05:03:16 GMT
References: <9007121332.AA02890@chiya.bellcore.com> <9007121800.AA01850@xap> <153@tots.UUCP> <269E07C3.604D@intercon.com> <64290@sgi.sgi.com>
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In article <64290@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes:
>In article <269E07C3.604D@intercon.com> amanda@mermaid.intercon.com
>(Amanda Walker) writes:
>+---------------
>| In article <153@tots.UUCP>, tep@tots.UUCP (Tom Perrine) writes:
>| > I hate to admit it, but the cell-phone (phone system) model of
>| > addressing does have many advantages for the *user*. No matter where
>| > you go, your logical address (phone number) follows you.
>| 
>| In all of the cellular systems I've used so far, roaming is only half
>| automatic.  In particular, to place a call to a roamer, you have to dial
>| the roamer access number for the area where they are, and then dial their
>| phone number.  This amounts to source routing, which is even more of a
>| pain for mobile destinations than it is for "static" ones.  Bleah.
>+---------------
>
>In fact, most of the current cellular romaing systems are 3/4-automatic... ;-}
>Automatic for the roamer dialing out; that's half. But now many (most?)
>cellular companies offer a hack such that if you dial a person's cellular
>number in their home area *and* they're currently known to be roaming
>somewhere (they've placed a roming call within the last 24 hours), the
>home area system will give you an intercept recording which tells you
>they're out of area... *and* gives you the roamer access number where
>they are. Sort of an ICMP Redirect...   ;-}    ;-}

Actually, GTE offers "Follow Me" Roaming in many foreign areas now.
The roamer simply registers in the foreign area (by dialing *18) and
all calls are forwarded automagically. It's pretty neat, but it sure
can surprise your friends... ;-)

-Greg