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AT&T Warns U-Verse Users of Service Disruption
Unless They Change Their Gateway Subnet by July 6
by Karl Bode 09:44AM Wednesday May 30 2012
AT&T is handling the migration toward IPv6 by -- shuffling U-Verse users around their IPv4 addresses? Users in our AT&T forum note that the telco has contacted many of them requesting that they make changes to their subnet. According to AT&T, the company is requesting that users who have configured their U-Verse gateway to use the - IP range need to change to an alternative IP range by July 6. Those who don't, an e-mail warns, -- "may potentially encounter a disruption in service."

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This user was told that the shift is because July 6 is going to be a major IPv6 migration date for IPv6, a migration AT&T has lagged behind in comparison to Verizon and Comcast. Other users believe AT&T is shifting to carrier-grade NAT -- a move that's ignoring RFC's, and is going to break network functionality (VPNs, outside access to home content) for many:
They are not "switching to IPv6" -- AT&T's dumbass plan for IPv6 is 6rd TUNNELING. (even AT&T COMMERCIAL services have laughable IPv6 deployment) IPv6 and IPv4 are completely different networks. There is no "NAT" involved... v4 and v6 hosts cannot directly communicate; it takes application aware proxies, no amount of header rewriting can make the two compatible. The only plausable reason for restricting 10/8 is the (idiotic) deployment of Carrier Grade NAT (CGN) inwhich customers no longer are assigned public IP addresses.
Though hey, users are being told now that they can avoid network problems by paying an extra $15 a month for a public IP address:
I was just told by AT&T 2nd tier support that this is indeed CGN, and that nat'ed customers will no longer be assigned a public IP address. You will be at least one layer, if not two layers down, which seems to also mean that access to services inside your home network will not be available to you outside, as well as breaking VPN. They have told me that for $15/month I can get a private IP address. Maybe that is the key here, getting another $15/month?
We've dropped a line to AT&T to get additional detail and will post any updates we receive.

99 comments .. click to read

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Shelton, CT

2 recommendations

reply to cowboyro

Re: If anyone bothered to read instead of bashing...

It's all speculation until there is an official word.
It can be as simple as not wanting to route the TV part through IPv6 when the time comes and keeping a 10.x.x.x range just for IPTV. Saves a lot on logistics, no need to do extensive testing with the receivers.

That VoIP Guy
East Lansing, MI

2 recommendations

reply to cowboyro
Unless you are using a game/chat service/file transfer service that requires you to have a public IP address.

AT&T will be giving out address to it's customers, hiding them all behind a few IPs, versus, giving them all public addresses. When you get a address, services from the internet can no longer contact you directly (you can, however start the conversation).

This is similar to being able to call somebody, but if they call you back, they get a busy signal.

Yet another genxer
Prattville, AL

2 recommendations

reply to cowboyro
said by cowboyro:

They would have realized it's about the *INTERNAL* IP/subnet, not the external IP of the gateway.

"The only plausable reason for restricting 10/8 is the (idiotic) deployment of Carrier Grade NAT" ... Ok so other than CGN why do you think AT&T would care that you're using 10/8?

The logical conclusion is they're wanting to use 10/8 on
the WAN side. Which of course would cause routing
issues if used on a LAN side.


Rancho Palos Verdes, CA

1 edit

2 recommendations

reply to Chewyrobbo

Re: 6RD Tunneling

Well, if they are going to use tunneling for IPV6 (I assume they don't want update their internal routers), they still fall into the IPv4 address shortage, because they would still need IPv4 to route the tunnels across their internal network.

So I'm going to guess that they are using carrier grade NAT to fix the problem of routing across their IPv4 network in order to support the 6RD tunnels.

This would mean you can still have a public IPv6 address, but setting up networks for legacy software will break. And that will be a pain in the short term when software is still transitioning.

I don't know if I should be too bothered about it. Whatever the carrier does to do implement IPv6, it will involve getting rid of your public IPv4 address anyways.

IPv4 is going to be legacy soon, and of course they will charge a premium to support legacy implementations.

I guess the only way around this is to fully transition all the services on your end to IPv6 before AT&T destroys support for your IPv4 address.

One other way to handle this problem is to make an IPv4 tunnel (on top of your 6RD tunnel... ... ...) to a proxy on the internet which will hold your public IPv4 address and through which the internet could access your network.......................