You can't really ignore the implications of NATs and firewalled nodes
that easily since most computers on the Internet these days are
behind NATs or firewalls.
But even if you do ignore their existence, the determining factor of
whether two nodes in a P2P network can communicate is that they know
of each other's existence, and that they know each-other's location
in information space (ie. not just their location in IP space).
It is not realistic to assume that every node in a P2P network will
have this information for every other node in the P2P network, at
least not if you want the network to be scalable, and so it is
necessary for nodes to select a subset of all other nodes in the P2P
network with which they can communicate.
Of course, the practicalities of operating a P2P network, which
include issues such as establishing cryptographic tunnels, and
dealing with NATs and firewalls, provide significant additional
motivation for restricting the subset of nodes with which a
particular node might seek to communicate with.
Ian.
On 10 Mar 2006, at 02:08, Jeff Rose wrote:
It seems like people are always putting arbitrary restrictions on
p2p systems and simulations in terms of connectivity, but is this
really necessary? Unless you are trying to use NATed nodes (assume
we can punch or route through a neighbor),just about any pair of
computers on the internet can be neighbors. In essence the
internet is a fully connected overlay graph. All DHT's and other
less-structured schemes are doing is deciding which links to send
messages down. So when you talk about "links existing" you just
mean that a given pair maintains some amount of regular
communication, or just that they know of each others existence in
the network? Maybe since you are coming from the freenet side of
things connectivity has a lot more meaning than in other schemes?
-Jeff
Ian Clarke wrote:
On 3/7/06, *Ranus* <[EMAIL PROTECTED]
<mailto:[EMAIL PROTECTED]>> wrote:
Hui Zhang has published a paper
named "Using the Small-World Model to Improve Freenet
Performance". It
should correspond to your idea, so maybe you could read that.
Be careful of this paper. If I recall correctly, most of their
results can be attributed to the fact that they ensured that links
existed between adjacent nodes in the graph, which obviously would
have a dramatic beneficial effect relative to a network where
local links may be missing as it means that in the worst case you
will do an exhaustive search for the node you are looking for just
by following local links.
Our findings, as presented in Oskar's thesis, are that Freenet-
style edge selection results in the desired degree of clustering
without "artificial" help.
Ian.
---------------------------------------------------------------------
---
_______________________________________________
p2p-hackers mailing list
p2p-hackers@zgp.org
http://zgp.org/mailman/listinfo/p2p-hackers
_______________________________________________
Here is a web page listing P2P Conferences:
http://www.neurogrid.net/twiki/bin/view/Main/PeerToPeerConferences
_______________________________________________
p2p-hackers mailing list
p2p-hackers@zgp.org
http://zgp.org/mailman/listinfo/p2p-hackers
_______________________________________________
Here is a web page listing P2P Conferences:
http://www.neurogrid.net/twiki/bin/view/Main/PeerToPeerConferences
_______________________________________________
p2p-hackers mailing list
p2p-hackers@zgp.org
http://zgp.org/mailman/listinfo/p2p-hackers
_______________________________________________
Here is a web page listing P2P Conferences:
http://www.neurogrid.net/twiki/bin/view/Main/PeerToPeerConferences
