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Date: Sat, 23 Mar 2013 11:24:41 -0400
Message-ID: <CA+8xBpfvTQ9pEygPmeSf0guOsECu6uecOG-KB=GVXtPKNo23ZQ@mail.gmail.com>
From: Jeff Garzik <jgarzik@exmulti.com>
To: Luke-Jr <luke@dashjr.org>
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Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] A bitcoin UDP P2P protocol extension
Precedence: list

On Sat, Mar 23, 2013 at 10:52 AM, Luke-Jr <luke@dashjr.org> wrote:
> On Saturday, March 23, 2013 10:42:26 AM Randy Willis wrote:
>> Introducing super-nodes with thousands of connected peers can greatly help
>> here.
>
> UDP is connectionless.
> I would hope any UDP bitcoin protocol doesn't try to emulate a connection. :/

It depends on the usage.  Simply broadcasting a TX or INV to a remote
peer does not require a connection, clearly...  but you probably want
to signal acceptance of those messages somehow.

But other uses, like subscribing to a broadcast, does require some
notion of an association.

In the rough draft, a parallel TCP connection with version/verack
sequence is required, and you may make use of it if a connection is
needed.

But that is just one approach.  A more robust, heavyweight UDP P2P
might be a hole-punching TCP alternative.  It's up to the community
and results of experimentation.

Bittorrent has evolved a full transfer protocol over UDP, to get
around firewalls and the like.
-- 
Jeff Garzik
exMULTI, Inc.
jgarzik@exmulti.com