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banquo
08-28-2005, 06:25 PM
Checked the stickied FAQ's, couldn't find an answer, maybe i'm stupid.

Whats the difference between a UDP tracker and a HTTP tracker? I'm sometimes presented with a choice.
{I}{K}{E}
08-28-2005, 06:29 PM
found this:

One advantage of UDP compared to http is that UDP messages are more compact and generate considerably less traffic.

:huh:
Dredpirate
08-28-2005, 06:38 PM
Short answer, it's just a different protocal. Supposed to save bandwidth.

I don't think all clients accept it. I know the latest Azureus does.

I tested it versus HTTP on a torrent from Demonoid a long time ago. Seemed to get better download speeds but could have been due to other things (like my imagination).
banquo
08-28-2005, 06:56 PM
Excellent, thanks.
99shassan
08-28-2005, 11:13 PM
doesn't udp not use windowing? so it should be faster because of that?
Dredpirate
08-29-2005, 04:28 AM
More streamlined, geared more towards data transfer.

Kinda FTP:// with better compatability.

Thats what I gather with a few reads.

I is not no engurner tho.

I'm good with lego's.
lynx
08-29-2005, 10:19 AM
UDP is "connectionless". That means you simply send the packet to its destination. If it doesn't arrive then it is lost, tough luck. If a response is required, that is another packet. Maximum 2 packets.

The alternative is TCP (not HTTP). TCP is connection oriented. You have to set up a connection (4 packets I think), send the data and receive the acknowledgement (2 more packets). If a response is required that's another 2 packets. Then the connection has to be closed (another 4 packets I believe). That's a total of at least 10 packets to send data to the tracker. Since it is only unimportant informational data that's a lot of overhead, especially for the tracker.

Just to be clear, HTTP may be used (I haven't looked into it that deeply) but since HTTP is a datastream protocol which is sent over a TCP connection it is the TCP which causes the overhead.
Dredpirate
08-30-2005, 04:02 AM
Yea,
It's just refered to as:

Download via HTTP: Tracker
Download via UDP: Tracker

on demonoid, (beleive thats where the question stemed from)

HTTP uses TCP so I guess thats why they say it that way.