[f-nsp] NetIron MLX-4 vs Juniper MX240

[George B.]

On Wed, May 12, 2010 at 12:50 AM, Rolf Hanßen <nsp at rhanssen.de> wrote:
> Hi,
>
> it looks to me you calculate with an amount of v6 routes similar to the
> number of v4 routes today and I thinks that this won't happen.
> For example: RIPE has assigned 5x IPv4 PA networks to us during the last
> 10 years but we only use one /32 v6 network. We furthermore had to split
> up those v4 assignments because we have a split network with several
> independent locations not connected together. This increased the number of
> prefixes we announce very fast.
> So the amount of v6 prefixes created from us will be much lower and I
> think other providers may have similar spaces they use.
> Even if you enable v6 for all networks currently using v4 I think total
> amount will keep below 100k routes.
>
> kind regards
> Rolf

For people who can qualify for a /32, particularly those who grew late
in the game, yes, there will be considerable consolidation.  What I
was more concerned about was smaller end user networks who currently
have a multi-homed /20 or smaller allocation that will be getting a
/44 or smaller v6 allocation and will keep both the v4 and v6
addresses.

There are a lot of multi-homed /24 nets out there that will become a
/24 v4 and a /48 v6 announcement. I suppose the vendors could help
things somewhat by not putting the entire 128 bits into hardware.
There is really no reason to have more than 64 bits for routing as the
last 64 bits are "supposed" to be host IPs ... but how many out there
are using /127 for point-to-points between routers?   You aren't
"supposed" to subnet anything smaller than a /64 but many do.

One thing I have noticed is that some networks are apparently
filtering anything smaller than a /32 from PA space but allowing
smaller nets from PI space designed for that purpose (down to a /48, I
think).  Anyone trying to multi-home a /64 is going to have a hard go
of it, I think, but someone is bound to try!

George