[Debtorrent-devel] Web Seeding

[Cameron Dale]

I've been doing some reading on the web (http) seeding implemented in
BitTornado and other clients. This seems like it will be very
promising for use as a fallback for debtorrent when faced with rare
packages.

Here is the BitTornado specification:

http://bittornado.com/docs/webseed-spec.txt

and the script required to be installed on the server to run it:

http://e.scarywater.net/bt/download/webseed-0.9a.zip

This is one of the downsides of this method, in that it requires http
seeds to install this script on their server. Currently this script
requires PHP and MySQL, which I'm not sure is something all mirrors
will have available, and also complicates the mirroring process for
mirrors that would like to support it.

It seems to me a better way, especially considering the infrastructure
already present in debian mirrors, is to just fall back to a regular
HTTP transfer. DebTorrent will already know the mirror address, and
the path to the file. One thing is it would be nice to be able to
request parts of a file, rather than the whole file, which will be
useful once packages are broken up into pieces. This requires mirrors
to allow range requests, which seems to be standard in HTTP/1.1 (and
apache), so I'm hoping it's commonly available on mirrors.

The disadvantage of this simplified method is it doesn't allow for
control by the http seed of what it uploads. BitTornado's script
allows for setting the maximum number of uploads and the maximum
upload rate, and doesn't require all the files to be publicly
accessible on the web. This seems unnecessary to me, especially
considering the mirror infrastructure debian has, where anyone can
download using HTTP if they want to.

Still, if anyone knows of a mirror with php and mysql where we could
test the web seeding implemented in BitTornado, let me know.

Cameron