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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Nachi/Welchia Aftermath
On Wed, Jan 21, 2004 at 12:11:43PM -0500, [email protected] wrote: > > > more generally... "if you want routing, buy a router." > > amen. > imho there can't be a better routing equipment than a real router :) But unfortunately, not true. A router is anything which makes decisions by performing a longest prefix match lookup against a layer 3 header, period. That "I route with a router and switch with a switch" nonsense is tired, usually covers for a lack of understanding of the issues involved, and prevents you from reaching the correct conclusion which is "I route with the device which is most appropriate for the task". There are some good routers, there are some bad routers, there are some TERRIBLE routers, there are even some routers which are good at some things and bad at others, but a router does not have to be a switch-turned-router to suck (at a specific task) any more than a switch-turned-router has to suck. For example, would you rather have the reassuring consistancy of a 7206VXR which tops out at 300Mbps come rain or shine, or might you prefer to use a Foundry BigIron which routes a couple gigabits under normal friendly non-stressful conditions and sits at 1% CPU? Of course, depending on the type of traffic and if you are from an older school of thinking your answer might very well be "I'd take the VXR", but the reality is that there is a lot more bandwidth out there than there used to be, and 300Mbps might just be an insignificant amount of traffic that is coming off 1 server for some people. Understanding the design limitations of ANY device, be it a software router, an asic based router with a prepopulated FIB, an asic based router with a CPU first lookup, a "hack on an ethernet cam" router, or two people with tin cans and a string yelling at each other in binary, is the first step to using it effectively. Understanding that the limitations of a "layer 3 switch" may make it ENTIRELY inappropriate for core routing work is a good beginning, understanding that a Juniper T640 may be entirely inappropriate for edge work or datacenter ethernet aggregation is a good middle ground, and understanding where and with what steps a "layer 3 switch" CAN be used effectively is even better still. Anyone who doesn't understand this is probably working for a bankrupt or soon to be bankrupt company. -- Richard A Steenbergen <[email protected]> http://www.e-gerbil.net/ras GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)
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