Re: [Softwires] Second working group last call for draft-ietf-softwire-public-4over6-04

[Peng Wu <[e-mail]>]

Hi Med,


On Mon, Dec 17, 2012 at 4:54 PM,  <[e-mail]> wrote:
> The feature described in this draft can be easily integrated in the current unified CPE effort (binding mode: MAP1:1/Lw4over6) or the document needs to be extended to cover the port restriction feature.


Comparing to address sharing transition mechanism, public 4over6 is
easier to implement and is more compatible to current network. On the
CE side, with public 4over6 there is no need to modify the DHCP(v4/v6)
client to support port-set allocation. ALG related implementations are
also not necessary.  On the BR side, DHCP server doesn't have to adapt
on how to maintain the IPv4 address + port-set pool. In general, there
are much fewer modifications to the current network elements.

On the other hand, with full IPv4 addresses assigned,  public 4over6
CEs can running application servers freely, which is of great
importance to the IPv6 transition for ICPs. As for regular users,
upnp,nat-pmp service can be supported much better with public 4over6.

Public 4over6 is simple and clean for ISPs, ICPs and end-users. We
simply put the features they need in these cases and call it done. If
we do it in the CPE draft and the port-set involved draft, we
overloaded it with features they do not need at all.

Cheers,
Peng