IPv6 delivery model to end customers

Mikael Abrahamsson swmike at swm.pp.se
Sat Feb 7 18:12:49 UTC 2009

On Sat, 7 Feb 2009, John Lee wrote:

> My IPv4 only deployment in 2001 used DSLAMs that had limited number of 
> active CPEs and DS3/T3 upstreams to the network. We used front end 
> Fore/Marconi ATM switches in front of Redback aggregation switches 
> connecting to Cisco 6509s and then GSR 12012s as the backbone routers. 
> The Redback authenticated with RADIUS servers using CHAP.

My ADSL2+ design I did in 2002-03 or so, used one vlan per customer in the 
DSLAM (first version was 1U 24 port ADSL L2 ethernet DSLAM, second 
generation was chassis based ADSL2+ DSLAM did 1024 vlans and had ~800 
ADSL2+ ports), vlans aggregated with an L3 switch doing GigE with the 
DSLAM, and one IP address per vlan (L3 switch was RFC3069 capable), no 
DHCP just statically provisioned when doing customer delivery. Worked 
great. Quite cheap as well. DSLAM was basically a L2 PVC->VLAN and PHY 
media converter.

But I wasn't talking (A)DSL. DSL is last century. I am talking VDSL2/ETTH. 
Security model there is to only have ethernet and IP, no PPP/ATM, no 
L2TPv3 or PPPoE. Let's skip the terms BRAS/LNS etc. Anything that 
terminates tunnels is expensive (apart from GRE/IPV6IP which the 7600 
seems to do very well, but I don't like tunnels. I like native). Most of 
the ETTH ports are 10/10, 100/10 or 100/100 (or even higher speeds) and 
100/10 costs ~30 USD a month. L2TPv3/PPPoE is not an option.

So, we have ~500k ports in my 9 million inhabitants country which are done 
via L2 switches in basements with CAT5/6 or fiber to the home. They use 
the security model I talked about before which I didn't really see a 
mention of in the list of IPv6 supported access models you listed. There 
are probably many millions more in Asia with the same model.

> IMHO rolling out IPv6 to the customer is a business decision now not a 
> technical one.

Well, I want to be able to do IPv6 at close to the same cost and security 
as I do IPv4 today. In your BRAS/LNS world it might be easy, but that's 
not the world I live in.

Mikael Abrahamsson    email: swmike at swm.pp.se

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