Specifications

10-23
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—Functional Overview
Figure 10-9 Example of Multiple LVCs CoS on the IGX
MPLS-Enabled VPNs
You can use MPLS to build an entirely new class of IP VPNs. MPLS-enabled IP VPNs (MPLS-VPNs)
are connectionless networks with the same privacy as VPNs built using Frame Relay or ATM VCs.
Cisco MPLS solutions offer multiple IP service classes to enforce business-based policies. Providers can
offer low-cost managed IP services because they can consolidate services over common infrastructure,
and improve provisioning and network operations.
Although Frame Relay and multiservice ATM deliver privacy and CoS, IP delivers any-to-any
connectivity, and MPLS on Cisco IP+ATM switches, such as the IGX-ATM LSR, enables providers to
offer the benefits of business-quality IP services over their ATM infrastructures.
MPLS-VPNs, created in Layer 3, are connectionless, and therefore substantially more scalable and
easier to build and manage than conventional VPNs.
In addition, value-added services, such as application and data hosting, network commerce, and
telephony services, can easily be added to a specific MPLS-VPN, the service provider’s backbone
recognizes each MPLS-VPN as a separate, connectionless IP network. MPLS over IP+ATM VPN
networks combine the scalability and flexibility of IP networks with the performance and QoS
capabilities of ATM.
From a single access point, it is now possible to deploy multiple VPNs, each of which designates a
different set of services (see Figure 10-10). This flexible way of grouping users and services makes it
possible to deliver new services more quickly and cost-effectively. The ability to associate closed groups
of users with specific services is critical to service provider value-added service strategies.
Host
Host
Edge
LSR-A
LVC 1-4
LVC 1-4
dest: 204.133.44.129
dest: 204.129.33.127
dest: 204.133.44.129
204.129.33.127
35245
ATM
LSR-2
IGX
ATM
LSR-5
IGX
ATM
LSR-4
IGX
ATM network with MPLS CoS
204.135.33.71
204.135.33.70
ATM
LSR-3
IGX
ATM
LSR-1
IGX
42
66
55
90
40
Edge
LSR-B
Edge
LSR-C
dest: 204.129.33.127
Host
204.133.44.129
41
42
43
50
51
52
53
43
44
45
67
68
69
56
57
58
91
92
93
(Precedence bits in IP
packet's ToS field set
by host in this example)
= labeled cell