LD> Date: Tue, 25 Apr 2006 09:43:51 +1000 LD> From: Lincoln Dale LD> I suggest you talk to some of the folks you work with that have to LD> deal with synchronous replication. LD> LD> In the world of storage networking & synchronous I/O, typically LD> anything higher than 1 msec round-trip latency is too high. This is a big can of worms that's probably OT for NANOG -- not to mention likely outside most readers' realm of experience. It _is_ an interesting field, though. I recommend the Morgan Kauffman book series as a good introduction. One also could argue the necessity and sufficiency of synchronous I/O in and of itself. There's a good deal of work, both published and strictly "in the lab" dealing with transactional commit mechanisms. Eddy -- Everquick Internet - http://www.everquick.net/ A division of Brotsman & Dreger, Inc. - http://www.brotsman.com/ Bandwidth, consulting, e-commerce, hosting, and network building Phone: +1 785 865 5885 Lawrence and [inter]national Phone: +1 316 794 8922 Wichita ________________________________________________________________________ DO NOT send mail to the following addresses: davidc@brics.com -*- jfconmaapaq@intc.net -*- sam@everquick.net Sending mail to spambait addresses is a great way to get blocked. Ditto for broken OOO autoresponders and foolish AV software backscatter.