Cisco Cisco IOS Software Release 12.0(22)S

To configure a router running IS-IS so that it generates and accepts only new-style type, length, and value 
objects (TLVs), use the metric-style wide router configuration command. Use the no form of this 
command to disable this feature.

metric-style wide [ transition ] [ { level-1 | level-2 | level-1-2 } ] 

no metric-style wide [ transition ] [ { level-1 | level-2 | level-1-2 } ] 

The MPLS traffic engineering image generates only old-style TLVs. To do MPLS traffic engineering, a 
router must generate new-style TLVs that have wider metric fields.

Router configuration

If you enter the metric-style wide command, a router generates and accepts only new-style TLVs. 
Therefore, the router uses less memory and other resources than it would if it generated both old-style 
and new-style TLVs.

This style is appropriate for enabling MPLS traffic engineering across an entire network.

This discussion of metric styles and transition strategies is oriented towards traffic 
engineering deployment. Other commands and models could be appropriate if the 
new-style TLVs are desired for other reasons. For example, a network might require wider 
metrics, but might not use traffic engineering.

In the following example, a router is configured to generate and accept only new-style TLVs on level 1:

Router(config-router)# metric-style wide level-1

(Optional) Instructs the router to accept both old- and new-style TLVs.

Enables this command on routing level 1.

Enables this command on routing level 2.

Enables this command on routing levels 1 and 2.

12.0(5)S

This command was introduced.

12.1(3)T

This command was integrated into Cisco IOS Release 12.1(3)T.

12.0(10)ST

This command was integrated into Cisco IOS Release 12.0(10)ST.