Looking for an IPv6 naysayer...
khelms at ispalliance.net
Wed Feb 9 15:50:39 CST 2011
On 2/9/2011 4:36 PM, Ken A wrote:
> 10/8 is the management network on my cable modem. The cable modem
> bridges your wan 'real' ip(s) through to your PC or router. At least
> that's how Suddenlink does it here. The customer is normally 'locked
> out' of the cable modem, unlike a dsl modem. The largest NATs are
> presumably w/mobile carriers. I've never been behind NAT (except one I
> controlled) on a consumer dsl or cable link in the US.
Agreed on the cable side (DOCSIS at least) but most of the DSL systems
I've seen are doing NAT on virtually all of the end user gear. Bell
South, SBC, Verizon, and Pac Bell are all doing or in the recent past
did most/all of their DSL installs this way. Bell South tried using a
brouter (only one I've seen in the wild) that did PPPoE on the WAN side
and then handed out the same address it was assigned via DHCP on the LAN
interface, but it was problematic (imagine that) and they stopped using
it some years before the AT&T purchase/merger.
The smaller telcos are almost universally doing NAT as well providers
like Alltel, Centurytel, Frontier, Finepoint, as well as the smaller
ILEC's simply don't do bridging on their CPE gear since they seldom had
their DSLAMs set up to deal with Q-in-Q or isolation methods. That's
not to say I don't know some that are the exception since I do know of a
few telcos that run PPPoE clients on the client PC and a handful that
did get port isolation working but they are not the norm in the US.
Vice President of Technology
ISP Alliance, Inc. DBA ZCorum
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