Comcast IPv6 Update

Rusty Dekema rdekema at
Fri Jun 1 14:06:32 CDT 2012

On Fri, Jun 1, 2012 at 2:06 PM, Seth Mattinen <sethm at> wrote:

> Forgive me if this is a stupid question since I've never been a cable
> guy, but what's physical difference between residential and commercial
> coax?

Not much, as far as I can tell. I'm a commercial ("Business Class" in
Comcast's terminology) coax customer; the CPE is just plugged into the
cable outlet in my apartment.

Comcast requires you to use the CPE they supply if you want a static IP up
through a /28 on commercial coax, which is kind of a shame. (Also, a /28
seems to be the largest block they will give you over commercial coax.)
Their CPE announces your address space into Comcast's network with RIPv2,
and presumably they don't wish to share the RIP credentials with small
customers. In the past, the admin ("mso") passwords were the same on all of
their commercial coax CPE so you could tinker if desired, but that is no
longer the case.

Some people have speculated that there are different QAMs (frequencies) for
commercial vs residential customers, but I have not seen any indication
that that is the case.

Finally, there is no 250 GB cap on commercial coax service, for now. (Not
that that's a physical difference.)


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