Multi-6 [WAS: OT - Vint Cerf joins Google]

Sun Sep 11 18:35:33 UTC 2005

On 11-sep-2005, at 19:06, Patrick W. Gilmore wrote:

>> 1. Give us a maximum number of multihomers.

> Unknown.  Somewhat less than the number of hosts on the Internet,  
> somewhat more than one.  My bet is closer to the latter than the  
> former.

Well, if you don't know the number of multihomers you can't be sure  
that their routes will fit inside a RIB or a FIB. It's that simple.

> In fact, I would think it's the same for v4.  Do you disagree?  And  
> if so, why?

I believe that in IPv4 today there is a lot of unrealized multihoming  
potential. Today, multihoming is difficult because you need address  
space and you have to set up BGP, and people think it's hard to get  
an AS number. If all of those difficulties were to go away, I think a  
lot more people would multihome. And of course the internet is  
becoming a critical resource for more and more organizations, which  
in itself should lead to more multihoming.

>> 2. Tell us how a routing table of that size (assuming 1 route per  
>> AS) will scale based on reasonable extrapolations of today's  
>> technology.

> Right, 'cause we all know tomorrow's problems need to be solved  
> with today's technology.  But let's try it anyway.

Who is using hyperbole now?

You're perfectly welcome to apply Moore's law, but a while ago there  
was someone who argued that he could install 50k routes in a second  
in his implementation. That's not what existing J and C gear can do,  
so I'm assuming there are reasons why their performance isn't better  
than it is today. So if you say you can handle 1M routes in 2 years  
and 8M in another 5, no argument from me. But if you make it 20M in 2  
years and 500M in another 5, I'll want to see how that's going to  
happen.

> As per RAS' post, reducing the growth of the table to equal the  
> growth of ASNs would be a huge win.

But a one time one, so it's meaningless. In v6 the AS-to-prefix ratio  
is already 1.4 so we're already there.

> A problem which is, in fact, solvable with "today's technology".

What is a problem that is in fact solvable with today's technology?

> So, despite your completely silly and unreasonable constraints  
> (kinda like "each home in the world being multihomed"), the problem  
> is still solvable.

You haven't produced either of the two figures required to show that  
multihoming scales, so you don't get to reach this conclusion.

> Keeping small providers, hosters, enterprises, schools, etc., who  
> do not want to be tied to a single provider from multihoming is a  
> huge loss.

I agree.

> And no, multiple IP addresses is not good enough.

What requirements do you have that are fundamentally incompatible  
with using multiple addresses?