Naive IPv6 (was AT&T UVERSE Native IPv6, a HOWTO)

Brian Dickson brian.peter.dickson at
Wed Dec 4 20:58:30 UTC 2013

On Wed, Dec 4, 2013 at 3:48 PM, Christopher Morrow
<morrowc.lists at>wrote:

> On Wed, Dec 4, 2013 at 3:43 PM, Brian Dickson
> <brian.peter.dickson at> wrote:
> > Except that we have a hard limit of 1M total, which after a few 100K from
> where does the 1M come from?

FIB table sizes, usually dictated by TCAM size. Think deployed hardware,
lots of it.
(Most instances of TCAM share it for IPv4 + IPv6, with each slot on IPv6
taking two slots of TCAM, IIRC. And a few other things also consume TCAM,
maybe not as significantly.)

(Newer boxes may handle more on some network's cores, but I don't believe
it is ubiquitously the case across the DFZ.)


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