Specifications

1-4
Cisco MGX 8850 (PXM45) and MGX 8950 Software Configuration Guide
Release 3, Part Number 78-14788-01 Rev. C0, January 2004
Chapter 1 Preparing for Configuration
Typical Topologies
Multiservice Edge Aggregation
Figure 1-2 shows the switch operating in a multiservice edge aggregation topology.
Figure 1-2 Multiservice Edge Aggregation Topology
In the multiservice edge aggregation topology, the switch is colocated with other ATM equipment and
communicates with one or more core switches at remote locations. The switch aggregates the traffic from
local ATM devices, and packages it for high-speed communications over the core.
Typically, multiservice edge nodes communicate with colocated ATM devices over relatively slow
broadband trunks such as DS3 and E3 trunks. The multiservice edge node communicates with core nodes
using relatively fast links such as OC-12, OC-48, and STM-16 trunks.
The Cisco MGX 8850 Release 1 node shown in Figure 1-2 is called a feeder node. For instructions on
configuring the Cisco MGX 8850 Release 2.1 switch to communicate with an Cisco MGX 8850
Release 1 feeder node, see Chapter 6, “Provisioning AXSM Communication Links.”
Cisco MGX 8850 and the Cisco MGX 8950 edge nodes also support virtual trunks as shown in
Figure 1-3.
Broadband trunks
38411
Core ATM
network
ATM router
(Cisco or third-party)
ATM edge devices
(Cisco or third-party)
Voice
Frame data
ATM data
Cisco
MGX 8850
(PXM1)
UNI or
NNI
Cisco
MGX 8850
(PXM1E)