
Explanation:
There are different switching methods to forward IP packets. Here are the different switching options:
Process switching:
All packets are examined by the CPU and all forwarding decisions are made in software...very slow!
Fast switching (also known as route caching):
The first packet in a flow is examined by the CPU; the forwarding decision is cached in hardware for the next packets in the same flow. This is a faster method.
(CEF) Cisco Express Forwarding (also known as topology based switching):
Forwarding table created in hardware beforehand. All packets will be switched using hardware.
This is the fastest method but there are some limitations. Multilayer switches and routers use CEF.