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p2psim: Roll Your Own P2P Protocol
Anonymous Coward writes "p2psim is a free, multi-threaded, discrete event simulator developed at MIT to evaluate and investigate p2p protocols. You can quite easily add your own p2p protocol and compare it with others to make sure it runs well before you write the real thing. p2psim runs in Linux and FreeBSD."
I've seen this program a short while ago, so feel I can comment :)
While it is a good idea, and can be worked on it does have some small problems, mainly that it isn't quite "dirty" enough. It tends to believe people will behave better than you'd expect them to, not be evil leechers and also not have very dodgy net connections which go up and down every 10 minutes (which to be fair happens to alot of people on ADSL and such like, their uploads get saturated and all their download connections drop because their ACKs aren't getting out)
Having said that, this is a good program, and I hope will be improved as one of the hardest parts about p2p networks is keeping up a good solid network without it taking up a significant proportion of the network, and nowadays few people want to risk running a server if they can avoid it...
Combination - fun iPhone puzzling
That works fine, if there are only one set of goals. But if you have more than one set of goals, you'll find that if you optimize for one set, you'll make it worse for the other set.
I imagine the technology used to simulate p2p netwroks can also be embeded in an app that could have a dynamic user configurable protocol one could change on the fly.
That would be the ultimate chaotic p2p network, and would be something ultimately funny to see go live.
-><- no
Whatever you do, don't look at the American railroad system. Which fell apart because the federal government paved interstates everywhere and let freight trucks run pretty much for free on them.
"How complete is it? I mean, does it contain a simulated RIAA that will come and sue you for distribution of copyrighted simulated material?"
Anybody who uses genetic algorithms, who 'breeds' computer programs rather than writing them, will tell you that the secret to success is good predators.
So yes, if you wanted to design a system for rating the quality of P2P protocols, one of the most important steps in that simulation is to have evolving predators, who try and intercept others' data, who try to slow the system down, who try to leech without sharing, etc. A system where data can be traced to an originator might score less than a system resiliant to this kind of attack.
The testbed mentioned in the article doesn't contain this sort of capability, but if you're involved in designing such networks, then it would be useful to dedicate a lot of effort to trying to attack the protocol using RIAA methods.
Read more about what a P2P application should have in its design.
Yawn... Another moron. Do you know, I actually found several sites where these Microsophist Litany monkeys had banned technical topics regarding p2p dev, protocols and their clients because they *think it's illegal because America"WemakechangestoyourfilesystemandOSwithouty ourpermissionandifyoudidthisyou'dbethrowninjailfor averylongtime"OffLine and Microsophists say so*. It amazes me how many of these morons exist.. they can be spotted by noting that they often can't tell the difference between a new protocol and an embrace&extend piece of crap, or that they think Microsoft Products are more cost effective and reliable than others (say, i don't know, the products used by most of the world's more sensible large banks, that is free and has regular updates and support from coders across the world for nothing.)