Comcast IPv6 Trials

tvest at tvest at
Thu Jan 28 13:11:35 UTC 2010

On Jan 28, 2010, at 7:47 AM, Richard Barnes wrote:

> What I've heard is that the driver is IPv4 exhaustion: Comcast is
> starting to have enough subscribers that it can't address them all out
> of 10/8 -- ~millions of subscribers, each with >1 IP address (e.g.,
> for user data / control of the cable box).

But then that begs the question of why lots of other very large retail Internet access providers have not indicated that they're committed to the same course of action (?).
They're certainly not the only provider that employs a public IP address-intensive access model, so where are the other retail IPv6 trial announcements/pre-announcements?

If they start appearing with some frequency real soon now, then maybe it's just a time-until-overflow issue. If not, then maybe there are other/better explanations.


> On Thu, Jan 28, 2010 at 12:55 AM, Kevin Oberman <oberman at> wrote:
>>> Date: Wed, 27 Jan 2010 20:59:16 -0800
>>> From: "George Bonser" <gbonser at>
>>>> -----Original Message-----
>>>> From: William McCall
>>>> Sent: Wednesday, January 27, 2010 7:51 PM
>>>> Subject: Re: Comcast IPv6 Trials
>>>> Saw this today too. This is a good step forward for adoption. Without
>>>> going too far, what was the driving factor/selling point to moving
>>>> towards this trial?
>>> SWAG: Comcast is a mobile operator.  At some point NAT becomes very
>>> expensive for mobile devices and it makes sense to use IPv6 where you
>>> don't need to do NAT.  Once you deploy v6 on your mobile net, it is to
>>> your advantage to have the stuff your mobile devices connect to also be
>>> v6.  Do do THAT your network needs to transport v6 and once your net is
>>> ipv6 enabled, there is no reason not to leverage that capability to the
>>> rest of your network. /SWAG
>>> My gut instinct says that mobile operators will be a major player in v6
>>> adoption.
>> SWAG is wrong. Comcast is a major cable TV, telephone (VoIP), and
>> Internet provider, but they don't do mobile (so far).
>> --
>> R. Kevin Oberman, Network Engineer
>> Energy Sciences Network (ESnet)
>> Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
>> E-mail: oberman at                  Phone: +1 510 486-8634
>> Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751

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