Appendix: Estimating Horizon Size

[skinydudesk8te]

The best approach is to introduce one or two messages solely for the purpose of communicating horizon size. Assume for simplicity that the Gnutella network is a tree, i.e., there is only one path between any two hosts. A key observation is that the number of hosts reachable from some host with TTL N is the sum of the number of hosts reachable from all its neighbors with TTL N-1. For formally, let H[A, n, B] be the number of hosts within n hops of host A that are reachable through B. Let H

 

[mmiller751]

Or at least give some more reference. Thanks.

 

[Nina Lee]

That 'quote' was from LimeWire's web site.

 

[*Pickles*]

Why don't you try BearShare, which calculates the horizon for you?

 

[>>BOb<<]

So I thought I might try and give my interpretation of the equations you posted.

Which means it's time to break out the ascii art:

First off there is one assumsion in these equations that is very important: there is only one route to a host.

A ---> N1 ---> O1

If there is more than one route to a host this won't work.

 

[Karrie Shmarrie <3]

those equations are really just a rough guess.

I always wanted some better data, so I started a little project. Though of it after seeing the stat page that Gnucleus nodes send out when a web browser tries to connect. Pretty cool, You can use a spider to "surf" the gnutella network. Only works with gnucleus and shareaza, but check it out if you want.

gnuMap project:
http://home.attbi.com/~gregory.bray/