Re: [Softwires] Is there any intest in re-visiting the Unified CPE Problem?

Qi Sun <> Thu, 21 August 2014 12:03 UTC

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From: Qi Sun <>
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Date: Thu, 21 Aug 2014 20:02:50 +0800
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Subject: Re: [Softwires] Is there any intest in re-visiting the Unified CPE Problem?
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Hi Ian,

I think this problem is still valid. 

IPv6 transition might be a relatively long process. Different requirements may be raised as time goes on. When remained IPv4 is quite scare, dynamic manage management of IPv4-IPv6 bindings might necessary. As the scale of IPv6 network enlarges and the number of recycled IPv4 addresses increases, static configuration of v4-v6 binding would be more convenient. Rather than replacing CPEs all the time, I would prefer a CPE prepares for those potential requirements. And a logic for mechanisms selecting is necessary.


On Aug 20, 2014, at 8:20 PM, <> <> wrote:

> Hi,
> At the last Softwire meeting in Toronto, I presented a question around whether the expired Unified CPE draft needs to be brought back to life ( There was little support for this during the meeting, so I’m taking it to the list to gauge if there’s wider interest in this problem.
> Currently in our network we are facing some of the problems that the Unified CPE intended to solve. Specifically, we will have DS-Lite, lw4o6 and public 4over6 in the operator network. The deployed HGWs may support DS-Lite only (RFC6204 compliant ‘off-the-shelf’ CPEs) or may be capable of all three. A individual HGW may also need to use different mechanisms at different points in its lifecycle (e.g. lw4o6 initially, but public 4over6 if the customer is located a full IPv4 address to use with non A+P compatible L4 protocols)
> So, my questions here are whether there are other operators (or vendors) that see problems of this type in their networks, and is there enough interest to open up the unified CPE problem again?
> Thanks,
> Ian
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