On Fri, Jun 13, 2003 at 01:25:06PM +1000, Martin Pool wrote: > On 12 Jun 2003, jw schultz <[EMAIL PROTECTED]> wrote: > > > Leave the communications protocol to the communications > > layer. You don't save anything by coding reordering and > > retransmission at the packet level; that is infrastructure. > > > > Connectionless is fine. Lightweight sessions is better. If > > you lose a connection a restart is possible. It is > > preferable to not have to authenticate and negotiate > > protocol versions and encryption with every message. > > > > Think in terms of transactions. Each transaction is atomic. > > If a transaction doesn't complete you have the means to > > roll-back and retry. If a connection breaks between > > transactions, or leaving a transaction incomplete, you start > > a new connection and pick up where you left off. > > I agree with all this. > > To extend on what jw says: > > I think it's fine to (if desired) negotiate SSL, authentication, and > compression at the start of a connection. They generally require > multiple round trips and it would be wasteful to do them more > frequently when per-connection is natural. > > On the other hand it would be nice if the client could pick up an > interrupted transfer halfway through the tree, rather than needing to > start from the beginning as rsync 2.x does.
Mind you, that means making the server lightweight with the client doing all the logic and a nearly stateless connection. Much like my earlier post on this thread posited. -- ________________________________________________________________ J.W. Schultz Pegasystems Technologies email address: [EMAIL PROTECTED] Remember Cernan and Schmitt -- To unsubscribe or change options: http://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html