[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: draft-wbeebee-ipv6-cpe-router-04 comments



On Fri, 27 Mar 2009, james woodyatt wrote:

Some vendors of consumer gear seem to feel the need to make the process of connecting their various appliances together to comprise a functioning network into a university dissertation defense. I think the more successful ones take a more subtle approach: they try very hard to make it as difficult as possible to connect devices together into a network that doesn't work. When the links between the nodes are all CAT-5 cables with RJ-45 plugs on each end, that problem is non-trivial and shouldn't be hand-waved away as not worthy of attention.

The solutions I have seen (and I think makes most sense) is to have a WAN port on the home device. This is the way it works with most NAT routers today, they usually have a single WAN port and then for instance, 4 LAN ports.

I know some providers who offer 5 IPv4 addresses per customer and who support customer L2 switches being connected, with the downside that all traffic between these devices usually end up going via the ISP (because local-proxy-arp is used for security reasons). For this reason, most people hook up a NAT device anyway, to keep the speed up within their home.

So, even though I agree that there should be no artificial limitations imposed, the recommendation for the most scalable solution would be to only support single IPv6 address on the WAN side of the customer device, and require it to do routing and support DHCPv6-PD. This saves TCAM resources on the ISP device which otherwise have to keep adjacancy information for potentially a large number of customer devices.

My scenario above is what I envision for ETTH (also VDSL2 and other ethernet framed alternatives).

--
Mikael Abrahamsson    email: swmike@swm.pp.se