how many locators?

[Andrew Partan <post-multi6@partan.com>]

How many locators should hosts have - or - how big is the global
routing table - or - where do you get your locators from?

As the number of locators per host goes up, the complexity of
choosing a pair of locations to use for a onnection goes up even
faster (probably as n**2).

So we probably want to limit the number of locators per host to a
smallish number.

Now hosts end up getting their locators from their upstreams (and
their upstreams' upstream?).  The question is how far up you go.
The further up you go, the more local paths out you have (probably
on the order of n**2), so the more locators per host you have.

If you go to the upstream's upstream's upstream, then you are
approaching approx the Tier-1 core, so the size of the global routing
table is approx the size of the Tier-1 core -- but at the cost of
having lots of locators per host.

If you go just one hop to the upstream to get the locator, then you
have just a few locators per host (basically the number of transit
connections per site), but you have a much larger global routing
table - approx the number of ISPs in the world.

Is this a reasonable size with reasonable growth factors?
	--asp