CLM> Date: Fri, 02 Jul 2004 04:18:07 +0000 (GMT) CLM> From: Christopher L. Morrow [ editted for brevity -- some punctuation/wording modified ] CLM> So, I thought of it like this. Rodney/Centergate/UltraDNS CLM> knows: [ snip enumeration ] CLM> [and] should know almost exactly when they have a problem CLM> they can term 'critical'... One essentially has a DNS network on top of IP network. Looks like O(N) with centralized monitoring, although it could approach O(N^2) if each server/pod cross-monitored all the others. CLM> The problem then becomes the "Hey, .org is dead!" From where CLM> is it dead? What pod are you seeing it dead from? Is it CLM> routing TO the pod from you? FROM the pod to you? The pod CLM> itself? Stuck/stale routing information somewhere on the CLM> path(s)? This is very complex, or seems to be to me :( I find your perception of complexity ironic. Yes, there's a good deal of splay. However, I suspect a network the size of UU also has a fair amount of peering splay, with a couple downstreams thrown in for good measure. ;-) However, I agree anycast has additional design implications: * Should servers/pods talk among themselves using mcast along pairs that follow L3 topology? Should N servers/pods each communicate with (N / 2 + 1) others, ignoring L3 topology? Fast poll the former and slow poll the latter? * If servers/pods communicate among themselves, should they use unicast addresses? anycast addresses? anycast addresses tunneled through unicast? * Each pod a stub? Each pod interconnected with an OOB OAM network? All pods interconnected with sizable backbone? Does multicast serve a purpose? 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.