Figure 1-2 Ip Vpn Service Example; Virtual Private Networks; Mpls Virtual Private Networks - Cisco BPX-BXM-155-8DX Installation And Configuration Manual

Chapter 1 The BPX Switch: Functional Overview

Virtual Private Networks

This section is a brief description of the BPX switch's support for Virtual Private Networks (VPN). For
additional information, refer to the Cisco MPLS Controller Software Configuration Guide
Conventional VPNs that use dedicated lease lines or Frame Relay Private Virtual Circuits (PVC) and a
meshed network (Figure 1-2) provide many advantages, but typically have been limited in efficiency
and flexibility.
Instead of using dedicated leased lines or Frame Relay PVCs, and so on, for a VPN, an IP virtual private
network uses the open connectionless architecture of the Internet for transporting data as shown in
Figure 1-2.
An IP virtual private network offers these benefits:
•
•
Figure 1-2
VPN B
VPN A

MPLS Virtual Private Networks

MPLS virtual private networks combine the advantages of IP flexibility and connectionless operation
with the QoS and performance features of ATM (Figure 1-3).
The MPLS VPNs provide the same benefits as a plain IP Virtual Network plus:
•
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Scalability
– Avoids VC mesh configuration
– Easy to add a new site since IP is connectionless
– Service provider handles router service management
Efficient
Rapid provisioning for networks
–
Supports any to any intranets
–
IP VPN Service Example
VPN A
VPN D
VPN C
VPN B
VPN B
VPN D
VPN D
Conventional VPNs, Leased Lines, etc.
Scaling and Configuration
– Existing BGP techniques can be used to scale route distribution
Each edge router needs only the information for the VPNs it supports
–
VPN C
VPN B
VPN C
VPN A
VPN A
VPN B
Cisco BPX 8600 Series Installation and Configuration
BPX Switch Operation
VPN A
VPN D
VPN C
VPN A
VPN B
VPN D
VPN D
IP Based VPNs
adding
new site
1-9