.
Things are getting better, but "L3-switches" pale in comparison to today's high-end routers on almost all fronts. If you take GigE out of the equation, modern "L3 Switches" are just as expensive as modern "core routers" - and routable, "mpls-able" L3 GE ports are _more_ expensive on "switches" than "routers" (see 4xGE OSM vs 4xGE GSR 'tetra' pricing). Media diversity, queuing performance, and FIB density is what really differentiates the two at this point, IMO.
[stuff deleted all over the place] Christian, I think you make the point very clearly, if you leave GigE in the equation things change a lot. Without it, none of this stuff walks too far. GigE is being used in all kinds of IX, LAN, and Metro environments that WAN circuits or at best FE used to be used for. This reduces the number of low speed and short-haul interfaces on most core routers immediately. 10GE still isn't a very far reaching technology yet (meaning, I can't seem to find one stable at > 26db) and SONET clearly wins in speed range for distance AFAIK. For networks that can engineer or re-engineer to GE or nxGE an L3 switch is going to do very well. Many support hardware rewrite for L2 forwarding, and newer ones are sporting real-router sized FIBs. Even in an IX environment, if you are only talking to peers, you can use an L3 switch with a 20,000 route FIB and know you'll never be defaulted to, and all of your BGP views at least 100 sessions can be aggregated on a little 1U box that costs $4000. You also protect your main router from a lot of nonsense that can be hw-filtered on the little box. If big routers could provide GE ports in higher densities at approximately the same price per port as a switch, the argument would be a dead one. Its expensive to privately (router) peer with 30 GE networks on a vendor J or vendor C router. Its relatively inexpensive to do it using an L3 switch. When talking about routers that need to aggregate lots of FR, ATM, or other WAN traffic -- or generally uplinking at greater than GE speed interfaces, you are probably better off [today] using a traditional router. I don't think anyone uplinking at 10GE speeds doesn't have a fair about of WAN connections. I don't think most people with lots of GE have many big core routers. I think its a self-selecting type of arrangement. Just my opinion, Deepak Jain AiNET