Net::BitTorrent::PeerID - Peer ID Specification
This document describes and provides examples of the Peer ID format used by the current release of the Net::BitTorrent module.
Net::BitTorrent
This non-standard format was developed to be URL-safe, unique to the implementation, and "human parsable."
There are three distinct sections to the Peer IDs generated: the header, the mid-section, and the signature. Consider this example:
NB004S-rogzGB1v--SVN
Here, NB004S is the header, -rogzGB1v is the mid-section, and --SVN is the trailing signature.
NB004S
-rogzGB1v
--SVN
Two uppercase characters ('NB') followed by three digits representing the SVN revision number with leading zeros, a single character potentially indicating stability and how the release was obtained, and a single hyphen (-).
NB
-
If the client is a CPAN build, the sixth byte is the capital letter 'C'. If the client is running a version checked out from public SVN (considered unstable), the sixth byte is the capital letter 'S'. Any other characters in the sixth byte are unsupported and may indicate a bad client.
C
Following that are eight random characters in the following range:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~
That is, all uppercase and lowercase letters, decimal digits, as well as the hyphen, period, underscore, and tilde (66 total). These are all characters allowed in a URL without encoded (referred to as "Unreserved Characters in [rfc://3986]) to reduce weight on the tracker during announce. On a popular tracker, every bit (and byte) helps.
This section is inspired by the pseudo-base64 set used by SHADOW's BitTornado client.
The final five characters may be random or static and should not be used in identifying the version of the client software. Some early versions even have my name in this spot. .:shrugs:.
Stable CPAN releases will have the sixth byte set to 'C' (capital letter 'c').
Unstable releases (referred to as DEVELOPER releases on PAUSE) on CPAN will have this bit set as if the user checked the source out from SVN, that is, the sixth byte will be 'S' (capital letter 's'). These will be released on CPAN with version numbers matching m[\d\.\d+_\d]. See the PAUSE FAQ section entitled "Developer Releases" (http://www.cpan.org/modules/04pause.html).
S
m[\d\.\d+_\d]
Version numbers will be some value less than one with the revision number in the three significant decimal places.
NB393C-04.9EraQ--SVN
This would be the stable CPAN release v0.393. The --SVN signature should be ignored.
v0.393
NB003X-9E-ayR6b-BT<3
Improper Peer ID; the sixth bit is neither 'C' nor 'S'. Possibly fake.
NB065S--09Egae69sy8W
Completely legal Peer ID generated by SVN/Dev r65.
Eventually, I would like to make a v1.0 release of Net::BitTorrent on CPAN. The information in this document and the means of generating the module's version number will need to reflect that.
Section 2.3. "Unreserved Characters" (http://tools.ietf.org/html/rfc3986#section-2.3)
(http://www.cpan.org/modules/04pause.html)
That is, the Creative Commons Attribution-Noncommercial-Share Alike 3.0 License (http://creativecommons.org/licenses/by-nc-sa/3.0/us/).
This specification is inspired by the documentation found on the BitTornado forum (http://forums.degreez.net/viewtopic.php?t=7070).
Sanko Robinson <sanko@cpan.org> - http://sankorobinson.com/
CPAN ID: SANKO
This document and the specification behind it are subject to change. All modifications will be documented in the "HISTORY" section of this file and in the Changes file included with this distribution. All versions of this file can be found in the project's svn repository.
This original documentation is covered by the Creative Commons Attribution-Noncommercial-Share Alike 3.0 License (United States jurisdiction).
This is the list of changes to this file and the specification it describes:
Current version - Feb 2nd, 2008 | r0010
Language and POD format cleanup. No specification changes.
First version - Feb 2nd, 2008 | r001
To install Net::BitTorrent, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Net::BitTorrent
CPAN shell
perl -MCPAN -e shell install Net::BitTorrent
For more information on module installation, please visit the detailed CPAN module installation guide.