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P2P & scalability

hey, i've got a question.  i remember reading about a year back how the p2p filesharing systems like gnutella et. al will all come crashing down because of the bottleneck with dial-up modems and what not.  it seems morpheus and the like are dealing with that by using 'supernodes,' which i gather are people with fat pipes (a step away from decentralization-so the original point still holds).

anyway, i recently saw that something like 20% of US internet users now use broadband (higher than i'd thought).  so my question is this-will the scalability issues still be there even if say eventually less than half of users use dial-up (which i can't imagine happening anytime soon-especially since new users will probably keep coming in on dial-ups as the internet expands)?  is there a point where there will be a critical mass of broad-band users so that the slower users won't drag down the system???

also-would there be anyway for some system to screen the speed of the connections as people log on to keep people say below a 200 K connection or what not off the system?

anyway, just curious.

razib khan
Sunday, February 17, 2002

Bored today, eh Razib?  Even too bored to use your Shift key?  :-)

>i remember reading about a year back how the p2p
>filesharing systems like gnutella et. al will all come
>crashing down because of the bottleneck with dial-up
>modems and what not.

Well, if I'm sharing a resource via my cable internet, why would it come crashing down because some people are still using dial-up?  I fail to see the correlation.

Also remember that any technical reading that does not come from a reference manual should be taken with a huge grain of salt.  Did this article perhaps come from an, ahem, "authoritative" source such as Ziff-Davis?  Or was it from Wired, the same guys who proclaimed in 1997 with great fanfare that the web browser was officially dead? 

http://www.wired.com/news/business/0,1367,35208,00.html


>so my question is this-will the scalability issues still be
>there even if say eventually less than half of users use
>dial-up

Is this really a scalability issue?  Won't the cable/DSL crowd simply avoid the dial-up users because of the slowness?  When you fire up Counter-Strike don't you automatically rule out the slowest ping servers?


>is there a point where there will be a critical mass of
>broad-band users so that the slower users won't drag
>down the system???

My crystal ball is still in for repairs, I'll let you know as soon as I get it back  :-)

What do you define as "critical mass"?  If you are referring only to the US then the number is a lot less than if you're referring to every country in the world that uses the Internet.  I assume that people in Bahrain and Pakistan would want to use Gnutella just as much as people in the US.

Feel free to go ahead flame me if I missed the point entirely.  See, I'm bored today also  :-)

The Man
Sunday, February 17, 2002

I feel safe in predicting that we can come up with larger files that we want to move around faster than we can build hardware to move them. There will always be bottlenecks.

Mike Gunderloy
Sunday, February 17, 2002

Your in luck, they are discussing the scalability of Gnutella over at Slashdot today http://slashdot.org/articles/02/02/17/0530222.shtml?tid=141

Matthew Lock
Sunday, February 17, 2002

Clay Shirky has written some interesting documents about this. "In Praise of Freeloaders" has an answer to your question:

http://www.openp2p.com/lpt/a//p2p/2000/12/01/shirky_freeloading.html


"Peers not Pareto" is also a good piece:

http://www.openp2p.com/lpt/a//p2p/2000/12/15/pareto.html

The documents raise some new questions but definitely shed some light on the scalability question.


Rikard

Rikard Linde
Sunday, February 17, 2002

http://www.aimini.com

aimini P2P software

Building Your Own P2P World.

A fascinating P2P software. You needn't have a domain name or static IP address, aimini application be capable of direct connect up in between users.

Alan
Wednesday, October 08, 2003

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