bittorrents port

[Kooldino]

Anyone know what port bittorents uses for uploading?

[uberlad]

81 isn't it? I thought it was just a clever wrapper over an http file transfer.

I may criminally insane however - it is wednesday.

Uberlad

[uberlad]

Unless you're running a tracker, which uses other ports.

I think.

[Jammrock]

I'm behind a firewall/NAT, can I use BitTorrent?

Yes, but you will get better performance if other peers can connect to you. By default, BitTorrent listens on port 6881, trying incrementially higher ports if it's unable to bind. It gives up after 6889 (the port range is configurable.) It's up to you to figure out how to poke a hole in your firewall/NAT.

http://bitconjurer.org/BitTorrent/FAQ.html

Jammrock

[Kooldino]

Hmm...So I'd have to have my router forward those ports to my main box If I wanted to use it?

[Ribbit]

I believe the port range Bittorrent will use has been expanded to 6881-6999. Of course it's configurable in any case.

No Kooldino, you don't have to have your router forward those ports. But you'll probably notice a nice speed improvement if you do. I certainly did.

[Gurm]

The issue I have with Bit Torrent is that nobody has written anything even remotely resembling an efficient client.

I have a connection that routinely turns in 250KB/sec. (kilobytes) downstream.

If I set an FTP going at 250KB/sec. and watch it. Solid. Stable.

Now I fire up Bit Torrent (any client). On a SINGLE TORRENT, pulling down 10K and putting out 15K, I have HIGH cpu usage (more than 50%) and the network SPIKES... dropping my FTP to 20K. That single Torrent, running at a combined 25K, uses up 225K of downstream bandwidth! ARGH!

And every client is like this. I have had to use Net Limiter just to stop the damn thing.

Gpar_

[Ribbit]

The 'official' Bittorrent clients are written in Python, an interpreted language. Some of the CPU usage is probably due to the crypto hash applied to every chunk downloaded as well.

I haven't seen the bandwidth inefficiencies myself.

[Gurm]

The "best" (I use that word VERY loosely) client I've seen for Bit Torrent so far is called "Azureus". It's written in Java so it has its own special kind of absurd overhead (damn Sun and their inefficient runtime!) but it's getting there. They had setbacks with their latest version which cut CPU/Network usage almost in half... but it'll be out again soon. Look for it at sourceforge.

Also, Shareaza works VERY well for Bit Torrent, but it's not nice - it's a leecher only as far as anyone can tell (they might have updated it since I tried it though). It's also incompatible with other Bit Torrent clients, so there's no resuming a torrent midway that you started with another client.

Also note that Bit Torrent is VERY insecure. Any client can get the IP addresses of EVERY OTHER CLIENT that's downloading from that Torrent. So if you wanna stay off the MPAA and RIAA's hitlists, don't get copyrighted material through Bit Torrent until someone hacks the protocol to allow anonymity.

Gpar_

[Jon P. Inghram]

I noticed another odd bit torrent glitch the other day when I was downloading a file that had a pretty large amount of people "sharing" it... it killed my internet access during the transfer when the number of connections got rather large. The transfer kept going at my cable's speed cap (3 megabit down, 256 kilobits up) as long as I kept my upload rate low enough not to swamp the modems upstream cap and jam up everything. It seems that the OS's networking system can only handle so many connections, and if they all fill up you're not going to be able to do anything until you close some, at least with Win98.

[Wombat]

Originally posted by Gurm


Also note that Bit Torrent is VERY insecure. Any client can get the IP addresses of EVERY OTHER CLIENT that's downloading from that Torrent. So if you wanna stay off the MPAA and RIAA's hitlists, don't get copyrighted material through Bit Torrent until someone hacks the protocol to allow anonymity.

Gpar_

First, "insecure" isn't the word you're looking for. It's a pretty secure protocol, actually.

Second, if that's a problem, stick to Freenet.

And peer guardian helps a little.

[Gurm]

JonPI:

It's not the OS, it's your cable modem. Sadly, DSL and Cable are NOT the same as T1, although their speeds are equivalent. The difference is readily apparent in this scenario - there are only so many control packets that can be sent, period. It matters not how much actual data you're transferring, you have a fixed amount of flow control. Period.

Wombat:

Peer Guardian helps NOT AT ALL with Bit Torrent. Get one of the advanced clients and you can see the IP of everyone downloading it - REGARDLESS of whether they are running Peer Guardian or not. And it's already been shown that the RIAA/MPAA don't need to see what's on your drive to sue you. They just have to see that you're downloading something copyrighted.

Now, WILL they sue? No, they've pretty much said that FOR NOW they're only suing people who are sharing out large quantities of files. So you're ok for the moment. But they could change their minds tomorrow - or may have already done so.

IF someone wants to see what's ON your machine, Peer Guardian is very helpful (although when running Bit Torrent, Peer Guardian will suck up HUGE amounts of CPU power processing all those packets), but if they just wanna see who's connecting to a tracker to download stuff... Peer Guardian don't do diddly.

Gpar_