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View Full Version : BitTyrant - A selfish Bittorrent client that improves performance



inman
01-04-2007, 12:38 PM
BitTyrant differs from existing clients in its selection of which peers to unchoke and send rates to unchoked peers. Suppose your upload capacity is 50 KBps. If you’ve unchoked 5 peers, existing clients will send each peer 10 KBps, independent of the rate each is sending to you. In contrast, BitTyrant will rank all peers by their receive / sent ratios, preferentially unchoking those peers with high ratios. For example, a peer sending data to you at 20 KBps and receiving data from you at 10 KBps will have a ratio of 2, and would be unchoked before unchoking someone uploading at 10 KBps (ratio 1). Further, BitTyrant dynamically adjusts its send rate, giving more data to peers that can and do upload quickly and reducing send rates to others.

BitTyrant is...

* Fast – During evaluation testing on more than 100 real BitTorrent swarms, BitTyrant provided an average 70% download performance increase when compared to the existing Azureus 2.5 implementation, with some downloads finishing more than three times as quickly.

* Fair – BitTorrent was designed with incentives in mind: if a user is downloading at 30 KBps, they should upload at 30 KBps. However, due to the unique workload properties of many real-world swarms, this is not always enforced. BitTyrant is designed to make efficient use of your scarce upload bandwidth, rewarding those users whose upload allocations are fair and only allocating excess capacity to other users.

* Familiar – BitTyrant is based on modifications to Azureus 2.5, currently the most popular BitTorrent client. All of our changes are under the hood. You’ll find the GUI identical to Azureus, with optional additions to display statistics relevant to BitTyrant’s operation.

Anyone gave it a try?
http://bittyrant.cs.washington.edu/

http://bittyrant.cs.washington.edu/images/screenshot.jpg

Ne'tu
01-04-2007, 12:43 PM
Based on Azureus, let's see how it's workng in the real world.

pECi
01-04-2007, 12:48 PM
sounds nice...might give it a try to see how it goes :D

Hanz™
01-04-2007, 12:55 PM
That was done as a project in CS on how to cheat on bittorrent.
Look at the PDF! There is stuff that is labelled: "4.3 Additional cheating strategies".

Cheating might work when there are only few people doing it, but it will just make everything slower if everybody does it. And private sites will ban you for doing so!

Ne'tu
01-04-2007, 01:03 PM
Hmmm, this is not a cheating client. I've looked through the PDF, but it's not about cheating there.

pECi
01-04-2007, 01:18 PM
well who said anything about using it on a large scale:whistling

Ne'tu
01-04-2007, 01:26 PM
I think they only want to improve performance of the normal Azureus client. Source code is of course available...

SIMRACK
01-04-2007, 01:26 PM
i think this client is banned from oink and bitmetv

Hanz™
01-04-2007, 01:29 PM
"Based on the insights gathered from a simple model of
BitTorrent's altruism, we built BitTyrant, a selfish client
that cleverly selects peers so as to optimize the amount
of download per unit of upload bandwidth. We found
that BitTyrant improves performance for all peers that
use it. Nevertheless, in practice, BitTyrant will hurt the
performance of individual swarms as high capacity peers
reach a point of diminishing returns and are incented to
either withhold their upload contribution or invest it in
other swarms. Low capacity peers do not enjoy such a
luxury. As the majority of peers have low capacity, they
will see degraded performance compared to BitTorrent
today."

meh.

edit: And yes, most large private trackers do not like such clients to be used as it deviates from the original bittorrent specification.

inman
01-04-2007, 02:19 PM
Private trackers are certainly going to ban this client. But it might come in handy with sites like demonoid where you have lots of peers but still won't connect to any.

lysine
01-04-2007, 02:40 PM
Hmmm, this is not a cheating client. I've looked through the PDF, but it's not about cheating there.

you obviously didn't read this one:
http://www.cs.washington.edu/homes/piatek/papers/BitTyrant_affiliates.pdf


Cheating with BitTyrant

The unfairness of BitTorrent suggests that tit-for-tat does not work as intended
and might be exploited by selfish users to improve performance.
We have built BitTyrant, a selfish client designed to do exactly this.


it breaks the protocol and is not good for swarms in general.

007™
01-04-2007, 04:53 PM
heard alot about this one, but i love my Utorrent :P

Solistca
05-27-2007, 04:31 AM
BitTyrant, form what I gather, was made for people with real connection speeds that actually give you an upload speed worth mentioning. ( I have have a dedicated fiber connection )

It's so I don't have to get completely raped by all the other users out there. I've noticed massive increases in my speed and still manage to seed more than 3.0 before I'm done downloading.

I think they're just figuring that if you're going to be carrying all the little leachers and slow upload connections form the states, you might as well GET what your downloading at speeds comparable to what you're uploading.

That is how BitTyrant actually works for me on a day to day basis.

Seems very fair to me. I'm sure the entire community would be pissed as hell if I decided to share 5KBs up with them like they do to me.

I constantly give back, and until I get on a private tracker that gives as well as it gets, I'll continue to use BitTyrant in public to get files.

tupac
05-27-2007, 10:31 AM
BitTyrant is based on modifications to Azureus 2.5, currently the most popular BitTorrent client.
:lol: This noobs heard about uTorrent? :wacko:

saulin
05-27-2007, 10:43 AM
This noobs heard about uTorrent?

I preffer Azureus over uTorrent any day. I have both installed but I use Azureus mostly. I have tried uTorrent since version 1.4 and I always liked Azureus better. Azureus has a lot of configuration options and I find it easy to tweak for max speed. I like the fact that it can be set to prioritize the first and last part of a torrent. It seems that you can start seeding much faster that way. Easy to use plugins with it and I like the stats screen much better. The only thing I didn't like was the memory usage but I found a good guide on how to reduce the memory usage.

As for BitTyrant it does sound kind of interesting. I might give it a try later on. Especially if it's based on Azureus.

tupac
05-27-2007, 10:56 AM
This noobs heard about uTorrent? I preffer Azureus over uTorrent any day. I have both installed but I use Azureus mostly. I have tried uTorrent since version 1.4 and I always liked Azureus better. Azureus has a lot of configuration options and I find it easy to tweak for max speed. I like the fact that it can be set to prioritize the first and last part of a torrent. It seems that you can start seeding much faster that way. Easy to use plugins with it and I like the stats screen much better. The only thing I didn't like was the memory usage but I found a good guide on how to reduce the memory usage.


Azureus is a bloated piece of s***. It eats a lot of memory and CPU compared to uTorrent.
And my post was about: "Azureus 2.5, currently the most popular BitTorrent client"
If you go on the peers page of a torrent on the site of a private tracker, you can see that 95% are using uTorrent, and only 2-3% are using Azureus. This is normal, since only very few people want to use a bloated piece of s*** like azureus.

Ratzy Rox
05-27-2007, 01:35 PM
Azureus is a bloated piece of s***. It eats a lot of memory and CPU compared to uTorrent.

Lawd, whatchoo got against using that RAM you paid for? I use utorrent when im on vista because RAM is at a premium then but on XP its Azureus all the way. Also - which site are you talking about?