IPv6 /64 links (was Re: ipv6 book recommendations?)

Masataka Ohta mohta at necom830.hpcl.titech.ac.jp
Mon Jun 25 07:06:50 UTC 2012


Justin M. Streiner wrote:

> I see periodic upticks in the growth of the global v6 routing table (a 
> little over 9k prefixes at the moment - the v4 global view is about 415k 
> prefixes right now), which I would reasonably attribute an upswing in 
> networks getting initial assignments.

As I already wrote:

: That's not the point. The problem is that SRAMs scale well but
: CAMs do not.

it is a lot more difficult to quickly look up 1M routes
with /48 than 2M routes with /24.

> If anything, I see more of a 
> chance for the v4 routing table to grow more out of control, as v4 
> blocks get chopped up into smaller and smaller pieces in an ultimately 
> vain effort to squeeze a little more mileage out of IPv4.

The routing table grows mostly because of multihoming,
regardless of whether it is v4 or v6.

The only solution is, IMO, to let multihomed sites have
multiple prefixes inherited from their upper ISPs, still
keeping the sites' ability to control loads between incoming
multiple links.

						Masataka Ohta




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