FS336Gv3 IPv6 Implemementation Issues

I thought I should post with an update on around 12 months of discussion with Netgear Support and my ISP (Zen Internet).

The FVS336Gv3 router implements IPv6 with a dual session approach not a dual stack approach (which implies a shared PPPoE session). This requires that your ISP support two concurrent sessions which is not a supported scenario with ISPs.  ISPs are implementing TR-187 as defined by the broadband forum (https://www.broadband-forum.org/technical/download/TR-187.pdf) - in particular Section 5.1.1

Single PPP dual stack IPv4/IPv6 Session
In the case of a dual-stack session, the mechanism adopted to provide IPv4 and IPv6 connectivity to the customer is based on the architecture described in RFC 4241 [18]. It combines the use of the  PPP  protocol  for  the  session  establishment  and  the  use  of  DHCPv6  and  DHCPv6  Prefix Delegation  for  the  configuration  of  the  IPv6  prefixes,  addresses  and  specific  parameters.    A single PPP  session  is  used to  carry  both  IPv4  and  IPv6  traffic;  the  device  that  initiates  the  PPP session  will  get  both  an  IPv4  address  and  at  least  one  IPv6  prefix.  The  details  related  to  the protocol stack and the message flows required to negotiate and configure IPv4 address and IPv6 prefix(es) will be described in the next sections. 

From an ISPs perspective I can see why they would only want to offer a single connection on a Radius server for accounting etc. It so happens that on one of my sites their DSLAM is incorrectly configured to allow multiple sessions hence the Netgear kit works in that site only.

Netgear have advised me that they WILL NOT change this behaviour and I note they do not appear to be a member of the broadband forum. So I would strongly advise people to check their ISP's IPv6 implementation before purchasing their kit.

Mark