jarvil at gmail.com wrote: > Node A has 6 links all normal speed. Node B has 6 links all normal > speed. Node A and B have a seventh high speed link between them. While > this would speed up there information exchange it would have no other > affect on the freenet because the phenomenon is localised. The 12 > normal links limit the high speed flow effects to the two nodes only > and it would not propagate further down the network.
Hi Jarvil, To some extent I agree with what you're saying, we should try to make use of fast links. However we're not just trying to solve the problem of getting data from A to B as quickly as possible - we're trying to get data from the source to the destination as fast as possible, where the link between A and B is only one part of the route. Here's the problem: what if B's route to the destination is nearly as long as A's (or longer)? Then moving the data quickly from A to B doesn't achieve much, or perhaps even makes things worse. So while it is important to make use of the available bandwidth, it's not a good idea to just send data down whichever link has spare capacity - we need to find some kind of tradeoff between short routes and fast routes. There are algorithms to solve this problem if you can see the whole network (maxflow), but we need a decentralised algorithm because each node only knows about its local neighbourhood. > I just cant get > past the fact that 10k/s x 7-8 nodes means a long time for large data > propagation. Bear in mind that data isn't streamed sequentially from point to point - each block is routed independently, so all the links will be used in parallel. Cheers, Michael
