The MPLS control plane software is enhanced to make MPLS more scalable and flexible. The MFI, which manages MPLS data structures used for forwarding, replaces the Label Forwarding Information Base (LFIB).

Note	The MFI and LFIB do not coexist in the same image. For a list of supported releases, see the "Feature Information for MPLS Forwarding Infrastructure."

Cisco software introduces a module called the MPLS IP Rewrite Manager (IPRM) that manages the interactions between Cisco Express Forwarding, the IP Label Distribution Modules (LDMs), and the MFI. MPLS IPRM is enabled by default. You need not configure or customize the IPRM. These commands are related to IPRM:

• clear mpls ip iprm counters

• debug mpls ip iprm

• debug mpls ip iprm cef

• debug mpls ip iprm events

• debug mpls ip iprm ldm

• debug mpls ip iprm mfi

• show mpls ip iprm counters

• show mpls ip iprm ldm

For information about these commands, see the Cisco IOS Debug Command Reference and the Cisco IOS MPLS Command Reference.

The following MPLS LSC and LC-ATM features are no longer supported, starting with Cisco IOS Release 12.4(20)T:

• MPLS LSC

• LC-ATM

• MPLS Scalability Enhancements for LSC and ATM LSR

• MPLS LSC Redundancy

• MPLS--OAM Insertion and Loop Detection on LC-ATM

• MPLS CoS Multi-VC Mode for PA-A3

• MPLS over ATM: Virtual Circuit Merge

• MPLS Diff-Serv Aware Traffic Engineering over ATM

• VSI Master MIB

Before upgrading to Cisco IOS Release 12.4(20)T, remove all the MPLS LSC and LC-ATM configurations from the routers in your network. If your core network has ATM links, you can use packet-based MPLS. See the MPLS Label Distribution Protocol Overview for more information. If you provide ATM access to customers, you can use the Any Transport over MPLS: ATM over MPLS feature. See Any Transport over MPLS for more information.

If you have MPLS LSC or LC-ATM features configured and you upgrade to Cisco IOS Release 12.4(20)T, the configuration is not accepted. The system displays “unrecognized command” errors for any commands that are no longer supported.

The following commands are no longer supported, starting with Cisco IOS Release 12.4(20)T:

• debug mpls atm-cos

• debug mpls atm-ldp api

• debug mpls atm-ldp failure

• debug mpls atm-ldp routes

• debug mpls atm-ldp states

• debug mpls xmpls cross-connect

• debug mpls xmpls errors

• debug mpls xmpls events

• debug mpls xmpls vc

• debug mpls xtagatm cross-connect

• debug mpls xtagatm errors

• debug mpls xtagatm events

• debug mpls xtagatm vc

• debug vsi api

• debug vsi errors

• debug vsi events

• debug vsi packets

• debug vsi param-groups

• extended-port

• interface xtagatm

• mpls atm control-vc

• mpls atm cos

• mpls atm disable-headend-vc

• mpls atm multi-vc

• mpls atm vpi

• mpls atm vp-tunnel

• mpls cos-map

• mpls ldp atm control-mode

• mpls ldp atm vc-merge s

• mpls prefix-map

• mpls request-labels for

• mpls traffic-eng atm cos global-pool

• mpls traffic-eng atm cos sub-pool

• show controllers vsi control-interface

• show controllers vsi descriptor

• show controllers vsi session

• show controllers vsi status

• show controllers vsi traffic

• show controllers xmpls

• show controllers xtagatm

• show interface xtagatm

• show mpls atm-ldp bindings

• show mpls atm-ldp bindwait

• show mpls atm-ldp capability

• show mpls atm-ldp summary

• show mpls cos-map

• show mpls prefix-map

• show xtagatm cos-bandwidth-allocation

• show xtagatm cross-connect

• show xtagatm vc

• snmp-server enable traps vsimaster

• tag-control-protocol vsi