[39073] in North American Network Operators' Group
Re: Cable Modem [really more about PPPoE]
daemon@ATHENA.MIT.EDU (Chris White)
Tue Jun 26 12:26:58 2001
Date: Tue, 26 Jun 2001 12:25:12 -0400 (EDT)
From: Chris White <cwhite@happyhappy.net>
To: William Allen Simpson <wsimpson@greendragon.com>
Cc: nanog@merit.edu
In-Reply-To: <3B38ADA5.68B26C4E@greendragon.com>
Message-ID: <Pine.BSF.4.21.0106261158590.2439-100000@cranky.happyhappy.net>
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On Tue, 26 Jun 2001, William Allen Simpson wrote:
> Chris White wrote:
> >
> > DHCP alone is not a viable option in this model. How do you get the end
> > user traffic to the ISP and back in a pure IP environment?
>
> Very easily. The ISP has a NAS at the headend (or even in every
> block). The cablemodem is a router that talks to the NAS, just as in
> any other environment. The NAS performs DHCP, just as in any other
> environment. The carrier provides commodity service, just as in any
> other environment. ;-)
The cable modem may be a router. A large number of DSL modems are not.
Most (if not all) 802.11b wireless endpoints are not (these are very
common in large scale deployments at the moment - long term viability is
another issue)
>
> For access control, you need IPsec. But you need IPsec for security
> and privacy anyway on a broadcast medium. This is really no different
> than wireless.
Agreed, but this is an additional client software on most end user systems
unless you have an IPsec capable router and it adds a substantial cost at
the termination point if you were to use IPsec tunnels to hand off the
customers to another provider.
>
> (Hint, we discussed this stuff in the IP/cable working group many years
> ago.... And I specified Mobile-IP to handle moving seamlessly between
> cellular and broadband networks back in '92-93. Should stop rehashing
> very old arguments.)
I looked into Mobile-IP for a wireless deployment...requires a client and
is not well supported at this time. Someday maybe...
>
> > In a wireless environment this becomes even more of a consideration as
> > most of the current hardware is limited in ATM or L3 functionality...
> >
> I shudder to think of trying to deploy ATM over wireless.
>
> I don't know why you would deploy at L3, it seems rather far away --
> but if you perhaps mean IP, then I don't expect wireless that isn't
> IP capable, going back to Tetherless Access Limited, and before that to
> amateur radio. Nobody would use it otherwise!
>
I was talking about the functionality of the client stations. Most are no
more than bridges at this time.
> William Allen Simpson
> Key fingerprint = 17 40 5E 67 15 6F 31 26 DD 0D B9 9B 6A 15 2C 32
>
