JS> Date: Mon, 8 May 2006 12:07:13 +0800 (CST) JS> From: Joe Shen JS> Could it be possible to implement IPv4 Anycast architecture for JS> radius server farm? Yes. JS> Could it be any problem with AAA procedure? UDP is anycast-friendly. Your biggest problems are likely to be authentication database replication/synchronization and merging accounting records... i.e., nothing really different from standard RADIUS deployments. Try ECMP if you want load balancing without the L4-ish gear. This implies routers between the NASes and RADIUS boxen, but you _did_ specify anycast. ;-) Load balancing is trickier when RADIUS servers and NASes live on the same network segment. You'll need something a la Windows Advanced Server or distributed 802.3ad. I know of no turn-key implementation of the latter; I played around with it a few years back, but the project was shelved before completion. Several modern *ix flavors include rudimentary 802.3ad support, so implementation should be easier these days. (Note that MAC-based technology strays away from "anycast" in the sense that it operates at L2 instead of L3.) HTH, 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.