Specifications

10-44
Cisco IGX 8400 Series Provisioning Guide, Release 9.3.3 and Later Releases
OL-1166-04
Chapter 10 Cisco IGX 8400 Series IP Service
IP Service Provisioning
To set up MPLS on an IGX node, complete the following tasks:
1. Configure the ATM LSR.
a. IGX switch (label switch slave): Configure the IGX for VSI.
b. Label switch controller (LSC): Configure the router with extended ATM interfaces on the IGX.
2. Set up label edge routers (LERs).
3. MPLS automatically sets up LVCs across the network.
Figure 10-17 shows a high-level view of an MPLS network. The packets destined for 204.129.33.127
could be real-time video, and the packets destined for 204.133.44.129 could be data files transmitted
when network bandwidth is available.
When MPLS is set up on the nodes shown in Figure 10-17 (ATM-LSR 1 through ATM-LSR 5, Edge
LSR_A, Edge LSR_B, and Edge LSR_C), automatic network discovery is enabled. Then MPLS
automatically sets up LVCs across the network. At each ATM LSR, VCI switching (also called “label
swapping”) transports the cells across previously-determined LVC paths.
At the edge LSRs, labels are added to incoming IP packets, and removed from outgoing packets.
Figure 10-17 shows IP packets with host destination 204.129.33.127 transported as labeled ATM cells
across LVC 1. The figure also displays IP packets with host destination 204.133.44.129 transported as
labeled ATM cells across LVC 2.
IP addresses shown are for illustrative purposes only and are assumed to be isolated from external
networks. Check with your network administrator for appropriate IP addresses for your network.
Figure 10-17 High-Level View of Configuration of an MPLS Network
Host
Host
Edge
LSR-A
LVC 1
LVC 2
dest: 204.133.44.129
dest: 204.129.33.127
dest: 204.133.44.129
204.129.33.127
35376
ATM
LSR-2
IGX
ATM
LSR-5
IGX
ATM
LSR-4
IGX
ATM network
204.135.33.71
204.135.33.70
ATM
LSR-3
IGX
ATM
LSR-1
IGX
42
50
66
55
90
40
Edge
LSR-B
Edge
LSR-C
dest: 204.129.33.127
Host
204.133.44.129