Re: [Bitcoin-development] Fwd: Service bits for pruned nodes

[Jeff Garzik <jgarzik@exmulti.com>]

On Tue, Apr 30, 2013 at 12:14 PM, Rebroad (sourceforge)
<rebroad+sourceforge.net@gmail.com> wrote:
> As part of a roadmap for block downloading, I think this may be a good time
> to look into providing an HTTP/HTTPS protocol for block downloading - this
> would also allow web proxies to cache blocks and thus make it more
> accessible, as well as cater for resumeable downloads.

Speaking generally, I've always been a supporter of finding new and
creative ways to store and transmit blocks.  The more diversity, the
less likely bitcoin can be shut down worldwide.

HTTP is fine, but you run into many issues with large files.  You
would need a very well defined HTTP-retrievable layout, with proper
HTTP headers along the entire path, if you want web caches to function
properly.  You need HTTP byte range support, HTTP 1.1 keep-alives, and
other features for resuming large, interrupted downloads.

The format currently used by bitcoind would be just fine --
blocks/blkNNNN.dat for raw data, size-limited well below 1GB.  Just
need to add a small metadata download, and serve the raw block files.

-- 
Jeff Garzik
exMULTI, Inc.
jgarzik@exmulti.com