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Cisco default value



CEF
 - Cisco Express Forwarding is enabled by default on most Cisco platforms running Cisco IOS software Release12.0 or later.
 - When Cisco Express Forwarding is enabled on a router, the Route Processor (RP) performs the express forwarding.

Enabling or Disabling CEF or dCEF on a Router
[no] ip cef
[no] ip cef distributed

When to Enable or Disable CEF on an Interface
The input interface determines the Cisco IOS switching path that a packet takes. 
 - CEF to be enabled on the incoming interface for packets to be CEF switched.
Because CEF makes the forwarding decision on input, you need
! on the ingress interface
[no] ip route-cache cef 

In contrast, because Cisco IOS builds a fast-switching cache entry after switching a packet, a packet coming in on a process-switched interface and going out through a fast-switched interface is fast switched. If you want to disable fast switching, use
! on the egress interface
no ip route-cache





Interface Bandwidth/ Delay:
INTERFACE bandwidth in kbits/s Delay in microseconds
(1 μs = 1/10^6 sec)
10 Mbps Ethernet 10'000 1000
100 Mbps Ethernet 100'000 100
1000 Mbps Ethernet 1'000'000 10
10000 Mbps Ethernet 10'000'000 1
Loopback 8'000'000 5000
Tunnel BW 100 50000
Tunnel transmit/receive BW
(only used with RBSCP - rate based satellite control protocol )
8'000
Token ring 16000 630
Fddi 100000 100
Serial 1544 20000
Low-speed serial:
115 20000
WIC on 1600/2600/3600 series,
sync/async interfaces on 252x,
sync/async serial modules on 2600/3600, etc..
ISDN BRI & PRI 64 20000
Dialer 56 20000
Channelized T1 or E1 n * 64 20000
Async tty line speed 100000