µTorrent Community Forums

Louif

Member

Local Peer Discovery Documentation

Is there any documentation about "Local Peer Discovery" that would allow inter-client interoperability ?

schnurlos

Moderator / Translator / Flaghunter

Re: Local Peer Discovery Documentation

http://download.utorrent.com/utorrent-help.zip and search for LPD:

LPD (Local Peer Discovery)
A method by which µTorrent attempts to discover new peers local relative to your computer's network. Local Peer Discovery makes use of IP multicast.

And some googling:
http://www.superjason.com/archive/2007/ … ature.aspx
http://www.bittorrent.com/btusers/guide … _Discovery

And why should that feature be interchangeable?
It just indicates peers within you network by IP or ISP.

Last edited by schnurlos (2009-10-30 00:34:44)

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deutsches Diskussionsforum | german discussion
deutsche Uebersetzung | german translation
Sonstiges

Ultima

Administrator

Re: Local Peer Discovery Documentation

... Louif isn't asking what LPD is -- he's asking for implementation details on LPD so that other clients can also implement it.

@Louif: There are no public specs that I know of.

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[size=0.85][ Tweaking Checklist | User Manual | BEE | MiniUI | µTA ][/size]

arvid

BitTorrent Developer

Re: Local Peer Discovery Documentation

in short: join the multicast group 239.192.152.143:6771 and listen for SSDP messages. Every 5 minutes, announce yourself to the multicast group by sending this message:

snprintf(msg, 200,
  "BT-SEARCH * HTTP/1.1\r\n"
  "Host: 239.192.152.143:6771\r\n"
  "Port: %d\r\n"
  "Infohash: %s\r\n"
  "\r\n\r\n", listen_port, ih_hex);

listen port is the port you accept incoming bittorrent connections on, ih_hex is the info hash of the torrent hex encoded.

more details:

http://libtorrent.svn.sourceforge.net/v … iew=markup

If you'd like to write a BEP for this (to be published on bittorrent.org), please send it to editor@bittorrent.org and I can put it up.

Louif

Member

Re: Local Peer Discovery Documentation

Thanks, this is very interesting information. I think I will be submitting a BEP, but I still need some time to think about this.

jch

Member

Re: Local Peer Discovery Documentation

Interesting -- so you're using a protocol that's not BEP-26.

Last edited by jch (2009-11-02 15:33:24)

Firon

Administrator

Re: Local Peer Discovery Documentation

I don't believe anyone ever implemented BEP26.

Ultima

Administrator

Re: Local Peer Discovery Documentation

Not necessarily an excuse, but to be fair...

--- 2007-04-05: Version 1.7 (build 1065)
- Feature: Local Peer Discovery

Created:    10-May-2008

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[size=0.85][ Tweaking Checklist | User Manual | BEE | MiniUI | µTA ][/size]

SawyerIII

Member

Re: Local Peer Discovery Documentation

So if LPD is a IPV4 multicast system, are there plans to use a IPV6 multicast system for "Global Peer Discovery"?