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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 24 Configuring BXM Virtual Trunks
Overview
Figure 24-1 Typical ATM Hybrid Network using Virtual Trunks
Benefits of Virtual Trunking
The following are the virtual trunking benefits:
•
Reduced cost by dividing a single physical trunk resources among a number of virtual (logical)
trunks. Each of these virtual trunks supplied by the public carrier is assigned only as much
bandwidth as needed instead of the full T3, E3, OC-3, or OC-12 bandwidth of an entire physical
trunk.
•
Migration of PNNI and MPLS services into existing networks.
VSI virtual trunks allow PNNI or MPLS services to be carried over part of a network that does not
support PNNI or MPLS services. The part of the network that does not support PNNI or MPLS may
be a public ATM network, or simply consist of switches that have not yet had PNNI or MPLS
enabled.
•
Utilization of the full mesh capability of the public carrier to reduce the number of leased lines
needed between nodes in the Cisco WAN switching networks.
•
Choice of keeping existing leased lines between nodes, but using virtual trunks for backup.
•
Ability to connect BXM trunk interfaces to a public network using standard ATM UNI cell format.
•
Virtual trunking can be provisioned through either a Public ATM Cloud or a Cisco WAN switching
ATM cloud.
Public ATM network
Leased line
Leased line
ATM-UNI
ATM-UNI
ATM-UNI
17721
Cisco
subnetwork
Cisco
subnetwork
Cisco
subnetwork
Summary of Contents for BPX 8650
Page 49: ...P A R T 1 The BPX Switch ...
Page 50: ......
Page 159: ...P A R T 2 Installation ...
Page 160: ......
Page 273: ...P A R T 3 Initial Configuration and Network Management ...
Page 274: ......
Page 311: ...P A R T 4 Configuring Connections ...
Page 312: ......
Page 487: ...P A R T 5 Troubleshooting and Maintenance ...
Page 488: ......
Page 533: ...P A R T 6 BPX Specifications ...
Page 534: ......
Page 555: ...P A R T 7 Appendices ...
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