Subject: Re: [sidr] RIB Size Estimation for BGPSEC

From: "t.petch" <[email-masked]>
Date: Thu, 2 Jun 2011 11:02:38 +0200

----- Original Message -----
From: "John Scudder" <[email-masked]>
To: "t.petch" <[email-masked]>
Cc: "Sriram, Kotikalapudi" <[email-masked]>; "sidr wg list"
<[email-masked]>
Sent: Tuesday, May 31, 2011 7:47 PM
> On May 27, 2011, at 11:50 AM, t.petch wrote:
>
> > RRG, before looking for some architectures that would solve the world's
routing
> > problems, did discuss the expected capacity of DFZ routers,  given the
expected
> > rate of growth of technology, so as to work out how long the IETF has got to
> > come up with something new.
> >
> > The consensus was that routers could not be expected to support more than 1M
> > entries in the RIB
> [...]
>
> Really?  I wouldn't put too much stock in that, given that current routers
support substantially more than 1M.
>
> > which is somewhat less than the 2.7M you expect in 2025.
>
> More than that too.
>
> Possibly you meant FIB and not RIB?  The reported numbers are wrong for that
too, though not as egregiously.

John

Thanks for the correction.  I was commenting on

15% yearly growth for # unique eBGP prefixes (377K in 2011 to 2.7M in 2025).

for which FIB would be a better acronym:-)  In the data that Philip Smith sends
out, I see a current figure of 357k or 360k and the RRG certainly saw a figure
of 1M as a practical maximum, with technology projected to go on evolving, so I
am unclear which numbers you see as wrong.

As to IPv6, I surmise that this will be a disaster area, with 60% growth perhaps
an underestimate.  On IPv6 lists, in the IETF and RIPE, there seems to be no
concept that handing out /48s to all and sundry could lead to an explosive and
untenable growth in the table.  Time and again I see comments to the effect that
IPv6 effectively removes the constraints on the assignment of prefixes with no
caveat about the impact on routers.  I just hope that IPv6 never catches on:-)

Tom Petch

> --John