Optimum Switching

Optimum switching is essentially fast switching with some caching optimizations. Like fast switching, optimum switching accomplishes the entire task of switching a packet during a single interrupt. The primary difference between optimum and fast switching is in the way the route cache is accessed. The optimum switching software is also crafted to take advantage of specific processor architectures. The fast switching code is generic, and is not optimized for any specific processor. Unlike fast switching, optimum switching is available only for the IP protocol.

Earlier in this chapter, you learned the Fast Cache is accessed using a hash table in earlier releases, and is accessed via a two-way radix tree in later releases. The ...

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