Specifications

1-9
Cisco MGX 8800/8900 Series Software Configuration Guide
Release 5.1, Part Number OL-6482-01, Rev. A0, January 25, 2005
Chapter 1 Preparing for Configuration
Typical Topologies
Multiservice Edge Aggregation
Figure 1-2 shows an MGX switch operating in a multiservice edge aggregation topology.
Figure 1-2 Multiservice Edge Aggregation Topology
The MGX 8850 (PXM1) node in Figure 1-2 is called a feeder node. In the multiservice edge aggregation
topology, the feeder node is co-located 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. MGX 8850 (PXM1E/PXM45) and MGX 8830 switches support feeder
connections from MGX 8230, MGX 8250, MGX 8850 (PXM1), and Cisco IGX nodes.
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.
Cisco MGX 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)