From: Lucas Gonze (lucas@lg.worldos.org)
Date: Sat Jul 01 2000 - 15:48:13 PDT
Though broadcast is the easiest analogy for beginners to grasp, once you
dig deeper you realize that it's wrong. The guts of the algorithm used by
Gnutella, Freenet and (plug) WorldOS (at www.worldos.org - free Ginsu with
every download!) is functional equivalence.
Broadcast is used to express the tendency of messages to follow branching
paths. But if every node in a message's path chooses to forward it to
only one other node, or if the message only reaches one single node, the
character of the system is unchanged.
What is new and useful is deciding that a query is successful if the
resources located are good enough to do the job. Any server node that can
satisfy this criteria is functionally equivalent to any other.
Functional equivalence is in contrast to identity equivalence. On the web
we go to foo.com (identity) and then look for the resource (function).
Search engines are so useful because they map functional requirements onto
identities. If there is a monopoly - like the NYTimes brand - then
identity is a good tool. If the resource is a commodity - like a table of
HTML tags or a tuning note - then functional equivalence is a better tool.
The difference between www search engines and infrasearch is (1) static
vs. dynamic data and (2) bulk indexing instead of spot indexing.
Broadcasting doesn't come into play at all unless one of the providers
downstream uses it.
This archive was generated by hypermail 2b29 : Sat Jul 01 2000 - 15:58:42 PDT