IPv6 CPE router requirements

It’s almost unbelievable: more than 10 years after the IPv6 specs have been completed, someone finally realized it would be a good idea to specify the minimum requirements for a decent IPv6 CPE router. While this document will not solve the lack of low-cost IPv6-ready CPE devices, it’s definitely a step in the right direction, more so as it clearly acknowledges the need for DHCPv6 (some people still believe SLAAC is the solution to every problem ever invented).

Here are a few highlights from the document:

  • The same mechanisms are used on the WAN side regardless of the physical media. With ND, SLAAC and DHCPv6 running on top of IPv6, there’s no need for link-layer-specific procedures (like the IPCP negotiations in IPv4).
  • The IA_PD option of DHCPv6 must be used to get the IPv6 prefix from the Service Provider.
  • When no other routing protocols are configured, Router Discovery must be used to find upstream routers and install static default routes.
  • DHCPv6 server must be supported on LAN interfaces (this is how you propagate DNS information to the end hosts).
  • The CPE router should support stateless filters (= access lists) and must filter obviously spoofed source IP addresses.

Now that the minimum requirements have been written, all we have to do is to wait for the vendors to implement them. Want to take a guess at when Linksys will support them?


  1. Linksys? They don't exist any more. It is the "you should have bought CISCO!" el cheapo brand from Cisco, nowadays.
  2. Few comments...

    1. DHCPv6 server shouldn't be a must on LAN side. In SLAAC there is some sort of RDNS (Recursive DNS) provisioning option. Some hw already supports this option (like Mikrotik router :)

    2. You said "someone finally realized". Well, that "someone" is Ole Troan from Cisco Norway, he is also editor of WT192 broadband forum paper, that deals with IPv6 requirements for CPE (same stuff as here). He is very good guy, knows exactly what he is talking about. Sometimes we exchange an opinion or two :)

  3. #1: You're right. Too bad they did not require support for RFC 5006 on the LAN side.
  4. Don't forget DHCP-PD! A cpe router would not be much use without it.
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