SlashDot: "Comcast Gunning for NAT Users"

Fri Feb 1 18:23:54 UTC 2002

Owen DeLong wrote:

> According to the excerpts from the TOS, VMWARE, Firewalls (other than
> an in-box firewall like BlackIce, etc.), WAPs and the like are already
> prohibited.  All of those represent termination of the connection on
> a non-comcast LAN.

I think that's reading too much into it. Clearly they allow for the use of
LOCAL networks. I mean, why would you need multiple IP addresses,
"expertise setting up a network", and so forth, if they didn't allow for
the use of user-side networks? The reference you mention seems to be
explicitly in the context of a REMOTE network, as in connecting 24x7 to a
pair of Exchange and Oracle servers, sucking up bandwidth all day long.

Let's look at this in their own terms. They allow frat houses, but I would
guess that not many of those only have 3 computers, yet they only provide
3 IP addresses, so NATs would almost certainly be required for most frat
houses. Conversely, they allow dorm rooms, but they don't want the
resident of that ROOM to resell or even provide connectivity to the rest
of the DORM.

In this context, I would say that if they are looking for NATs at all,
they are looking to see if there are dozens of computers hooked up
somewhere that shouldn't be, such as a dorm room reselling pipe, or a
residential house providing connectivity to the entire neighborhood. My
guess would be that they are only looking for this after they have noticed
a utilization issue.

I mean, if you are using 100x the bandwidth of other people in your
neighborhood, they want to figure out which provision you are PROBABLY
violating. Are you running a warez server (forbidden)? Are you providing
connectivity to others in your neighborhood (forbidden) (presumably via
NAT, since they only give you 3 IPs)? Are you running a small business out
of your house (forbidden)?

That seems to be the only context that has any significance in any of
this. Keep your utilization at a point where they don't have to upgrade
pipes AND don't have to listen to complaints from your neighbors, and they
probably won't care what you do with it.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/