RE: IPv6 Address Planning

[Cody Lerum]

Makes sense. However the PTP addresses need to be internally visible
from an NMS perspective in our network.

-C

-----Original Message-----
From: James [mailto:james@towardex.com] 
Sent: Tuesday, August 09, 2005 12:13 PM
To: Cody Lerum
Cc: nanog@merit.edu
Subject: Re: IPv6 Address Planning

On Tue, Aug 09, 2005 at 11:24:22AM -0600, Cody Lerum wrote:
> 
> Currently we are in the process of planning our IPv6 addressing schema

> for our network. We are a service provider with around 20 core 
> routers, and several hundred enterprise customers. These customers 
> currently connect back to our core via a separate VLANs or channelized

> DS1/DS3/OC-X type interfaces. Thus currently lots of /30 IPv4 blocks.
> 
> Our address allocation is 2001:1940::/32
> 
> Here is our current plan, but we are looking for suggestions from 
> people who have been down this road before. The plan is to break out a

> /48 for our organization. Then break out the first /64 for loopbacks, 
> and the next /64 for point-to-point connections. The PTP /64 then 
> breaks out further into 1 /80 for core links, and 1 /80 for each of 
> our distribution sites. Within these /80's are individual /112's for 
> PTP links. What this will allow us to do is aggregate each sites PTP 
> connections into /80's within our IGP.

The way we do it currently are as follows:

Reserve a /48 for backbone pointopoints (eg. 2001:4830:ff::/48) in US,
fe::/48 in EU.  Reserve a /48 for loopbacks, and use /128s for each
loopback out of that.  As for point to point links, we currently use
simple /64 subnets for each point to point (i.e. 2001:4830:ff:1500::/64,
etc where ::1 and ::2 are routers on either side of the circuit).

>From there, we also have a /48 allocated per each POP for transfer
networks at that location for peering via pni and customer hand-offs.
Each xfer net is broken off as /64 out of that /48.  We currently do not
perform any PTP link aggregation in our IGP, we simply ensure only
passive-interfaces are announced to IGP, thus PTP links are not even
present in the IGP table (only loopbacks and xfer nets/bgp next-hops
are).

It is not perfect but works well currently and scales just fine for us.


<shameless plug>

You may also find the ipv6-ops list helpful for v6 rollout discussions:
  http://lists.cluenet.de/mailman/listinfo/ipv6-ops

</shameless plug>

James


--
James Jun
Infrastructure and Technology Services
TowardEX Technologies
Office +1-617-459-4051 x179 | Mobile +1-978-394-2867 james@towardex.com
| www.towardex.com