Cisco Cisco IOS Software Release 12.0(22)S

Now the extended command is

ip rsvp bandwidth x y sub-pool z

where x = the size of the global pool, and z = the size of the sub-pool.

(Remember, the sub-pool’s bandwidth is less than—because it is part of—the global pool’s bandwidth.)

The old command was

tunnel mpls traffic-eng bandwidth b

where b = the amount of bandwidth this tunnel requires.

Now you specify from which pool (global or sub) the tunnel's bandwidth is to come. You can enter

tunnel mpls traffic-eng bandwidth sub-pool b

This indicates that the tunnel should use bandwidth from the sub-pool. Alternatively, you can enter

tunnel mpls traffic-eng bandwidth b

This indicates that the tunnel should use bandwidth from the global pool (the default).

To establish a sub-pool TE tunnel, you must enter configurations at three levels:

the device (router or switch router)

the physical interface

the tunnel interface

On the first two levels, you activate traffic engineering; on the third level—the tunnel interface—you 
establish the sub-pool tunnel. Therefore, it is only at the tunnel headend device that you need to 
configure all three levels. At the tunnel midpoints and tail, it is sufficient to configure the first two levels.

In the tables below, each command is explained in brief. For a more complete explanation of any 
command, refer to the page given in the right-hand column.

At this level, you tell the device (router or switch router) to use accelerated packet-forwarding (known 
as Cisco Express Forwarding), MultiProtocol Label Switching (MPLS), traffic-engineering tunneling, 
and either the OSPF or IS-IS routing algorithm (Open Shortest Path First or Intermediate System to 
Intermediate System). This level is often called global configuration mode because the configuration is 
applied globally, to the entire device, rather than to a specific interface or routing instance. (These 
commands have not been modified from earlier releases of Cisco IOS.)

You enter the following commands:

Router(config)# ip cef distributed

Enables Cisco Express Forwarding—which accelerates the flow 
of packets through the device.

Router(config)# mpls traffic-eng tunnels

Enables MPLS, and specifically its traffic engineering tunnel 
capability.