Cisco Express Forwarding
Cisco Express Forwarding (CEF) is an advanced layer 3 switching technology used mainly in large core networks or the Internet to enhance the overall network performance.
What is no ip cef?
To disable central Cisco Express Forwarding on a router and on all interfaces on the router, use the no ip cef command.
What is ip cef optimize neighbor resolution?
ip cef (Cisco Express Forwarding) has different functions for speed of packet process (l2 or l3) done in hardware. If you erase this command it will affect the speed of resolving arp for directly connected hosts, but not its functionality. So cef neigh resolution means speed of arp done in hw using adj table.
What is ip cef Cisco command?
Cisco Express Forwarding, CEF is advanced Layer 3 IP switching technology used on cisco router and switch. It is a feature that allows a router to quickly and efficiently make a route lookup. CEF optimizes routing table lookup by creating a special, easily searched tree structure based on the IP routing table.
How does ip CEF work?
From a 500 foot view CEF is a method the router uses to forward packets, without utilizing any CPU cycles. CEF works by creating two tables: The Adjacency table maintains the layer 2 forwarding information for each FIB entry eliminating the need for the router to send out ARP requests.
How do I disable CEF?
How do I turn on my CEF?
To enable CEF, use the ip cef command in global configuration mode. Enable dCEF when you want your line cards to perform express forwarding so that the route processor (RP) can handle routing protocols or switch packets from legacy interface processors.
What command can be used to globally enable CEF on a router?
To enable CEF, use the ip cef command in global configuration mode.
Which table is generated from the routing table in CEF?
CEF works by creating two tables i.e. Adjacency table and FIB. On the other hand, IP routing table contains next hop exit information, AD, Metric and best route toward destination.
