I agree with many on this list about the use of HTTP to transfer files...I
really don't get why people think bitTorrent is special; and I'm even more
confussed considering HTTP is Text based and to transfer data you have to
convert it to base64 and back again. HTTP was meant to transfer HTML...its that
simple. People are klugding HTTP b/c they 1. don't have access to browser
source code, 2. don't have the skills to write their own. Basically if we could
rewrite history and create a new protocol to handle these differences; that
would be optimal...but never happen. Its just basically fighting the ignorant.
my opinion of course.
Adam Fisk <[EMAIL PROTECTED]> wrote:
Hi Peter- I've come to this view after closer work over the last several
years with the IETF and more intimate experience with protocol design in
implementing various IETF protocols, particularly within the SIP family. My
initial forays into protocol design came from working on many different
protocols on Gnutella, and some of the Gnutella protocols suffer from the same
problems as BitTorrent.
In a nutshell, well-architected protocols are designed to do very specific
things well. This allows each protocol to evolve independently, with each
protocol yielding control to others in the stack at the appropriate levels of
abstraction. In SIP, this approach is readily apparent and strikingly
effective, with SIP exclusively establishing sessions, leaving the Session
Description Protocol (SDP) to describe the session, the MIME specifications
within SDP to describe the type of media the session will handle, and with STUN
and ICE handling thorny NAT traversal issues. Each protocol is independent of
the others, with these discrete building blocks leading to incredible
flexibility as the protocols evolve. It also allows discrete open source
projects to be extremely focused in the protocols they implement.
One key to these principals is to re-use protocols effectively. With everyone
in the world implementing and understanding MIME, SDP can interoperate much
more easily if it also uses MIME. For file transfers, HTTP is the universal
standard for lots of good reasons. BitTorrent uses effectively a proprietary
file transfer protocol, thereby breaking interoperability with the rest of the
Internet. While BitTorrent is "open" in the sense that anyone can implement
it, it's almost worse than being a closed protocol because it doesn't fit in
with any of the very well-designed other protocols out there. It would never
have a chance to interoperate with, say, SIP or XMPP because it just implements
everything as it damn well pleases.
I say the features of BitTorrent don't come anywhere near justifying this
because the primary reason for breaking HTTP is tit-for-tat support.
Tit-for-tat is basically providing incentive to keep your client running.
That's more or less fine, but that piece should not be coupled to file
transfers. At a protocol design level, that's just insanity. It also comes at
a tremendous cost. Every web server on the planet is now an invalid source for
a file! Excluding the most powerful computers on the Internet from the
distribution system doesn't seem like a sound design decision, particularly for
the poorly conceived tit-for-tat justification described above.
I actually have lots of other issues with BitTorrent, but the protocol layering
issue might be the biggest.
-Adam
On 1/5/07, Peter K Chan <[EMAIL PROTECTED]> wrote: Adam,
Your assessment of BitTorrent caught my attention.
How is BitTorrent "breaking interoperability with the rest of the
Internet?" Why is it that the unique features of BT "don't come anywhere near
justifying" it?
Peter
_______________________________________________
p2p-hackers mailing list
[email protected]
http://lists.zooko.com/mailman/listinfo/p2p-hackers
You don't get no juice unless you squeeze
Lemon Obrien, the Third.
http://www.tamago.us_______________________________________________
p2p-hackers mailing list
[email protected]
http://lists.zooko.com/mailman/listinfo/p2p-hackers
