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Vendor support for IS-IS is quite limited - many options for OSPF.

Depends on the vendor.

I think you misunderstood his point: it's not the knobs, but the vendors. Generally, when you're trying to integrate random crap into an otherwise well-structured network, you'll find OSPF available, but very rarely IS-IS. I run into this a lot in the security appliance space, where you want your security appliances to either learn or advertise routes internally (VPN tunnel reachability is a big reason for this), but also in devices such as load balancers and other middlebox cruft that occasionally needs to participate in routing advertisement/subscription. Some vendors grab random open source routing protocol code that includes everything and dump it into their boxes, usually accessible via an entirely separate configuration interface; this can include IS-IS, but these implementations rarely actually work as they are usually "check list" implemented for a specific RFP or customer and never get widely tested. The ones who actually care about making it work almost always include RIP and OSPF, with a few shout-outs to BGP. IS-IS (and OSPF v3) rarely makes the cut. In a world where you are doing well-controlled Cisco/Juniper/etc networks with fairly homogeneous code bases, the engineers get to have this discussion. When you have to link in devices for which routing is not their primary reason to exist, your options narrow very quickly. It's not ideal; that's just the way it is. jms -- Joel M Snyder, 1404 East Lind Road, Tucson, AZ, 85719 Senior Partner, Opus One Phone: +1 520 324 0494 jms@Opus1.COM http://www.opus1.com/jms