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The Cisco MGX 8250 Wide-Area Edge Switch is a carrier-class Edge Concentrator that integrates multiple services and service management capabilities on a single platform. It cost-effectively delivers Frame Relay, Circuit Emulation (CE), ATM cell relay service, IP VPNs (VoIP, VoATM) and voice at high volume and with high scalability—from DS0 to OC-12C/STM-4 speeds.
The MGX 8250 chassis accommodates narrowband interfaces from DS0 with port density scaling to more than 1000 DS1s of service interfaces.
The MGX 8250 supports both Layer 2 and Layer 3 services in the same Edge Concentrator.
Services include:
The MGX 8250 platform can also support a wide range of services over narrowband and mid-band user interfaces, mapping all the service traffic to and from ATM, based upon standardized interworking methods.
The MGX 8250 switches support up to 192 channelized or unchannelized T1 and E1 interfaces on a single switch, providing support for Frame Relay UNI and NNI; ATM UNI, NNI, and FUNI, Frame Relay-to-ATM network interworking; and Frame Relay-to-ATM service interworking. Using the Service Resource Module (SRM), multiple T1 interfaces can be supported on physical T3 lines. Frame-based services on T3 and E3 high-speed lines are also supported. The MGX 8250 switches also support the use of Inverse Multiplexing for ATM (IMA) to provide ATM trunking below T3/E3.
Physically, the MGX 8250 consists of cards in a 19- or 23-inch rack-mountable shelf. MGX 8250 hardware includes:
MGX 8250 software (presented in Chapter 6) is partitioned into four groups that are distributed across the PXM and the service modules:
The MGX 8250 switch performs both end-to-end and local traffic management to optimize QoS (described in Chapter 8).
System performance metrics of the MGX 8250 are presented in Chapter 9.
The MGX 8250 conforms with virtually all relevant networking, safety, environmental, radio frequency, and EMC standards.
The MGX 8250 switch is a multiservice, carrier-class platform that aggregates IP, Frame Relay, ATM, voice, and private lines at the edge of the network.
The MGX 8250 supports the networking protocols required to integrate into an existing BPX network, so an MGX 8250 switch can be deployed as a feeder of a BPX 8600 series service node.
By enabling deployment of multiple services on a single platform, this capability allows carriers to customize deployments across diverse point-of-presence (PoPs) while maintaining common inventory and operations support.
Configuring as a feeder to BPX networks (see Figure 1-1) has several enhancements:
The MGX 8250 can be deployed as a stand-alone switch, providing "cross-connect" connections between UNI and NNI ports. Traditionally, this would be used in a concentration-type mode, allowing standards-based adaptation and concentration of multiservice traffic onto one or more high-speed ATM interfaces. This enables the MGX 8250 to interface to a multivendor ATM network, or to any other ATM attached device (such as a Cisco 7200 or GSR router LS1010, MSR 8450, and so on).
The MGX 8250 interfaces to the ATM equipment using a standard ATM UNI or NNI.
The MGX 8250 is well suited as an edge device in an MPLS network. The MGX 8250 can act as an edge label switch router for support of IP traffic. At the same time, the MGX 8250 can also support Layer 2 services as a BPX feeder or as a multiservice stand-alone switch.
As a component of the BPX 8680-IP universal service node, the MGX 8250 is capable of forwarding traffic into the BPX MPLS network by acting as a multiservice feeder and supporting up to 12 edge label switch routers in a single chassis.
The MGX 8250 can also be used to aggregate and separate the IP traffic onto a pure IP backbone, distinct from the ATM backbone it uses for Layer 2 services.
As a Label switch or a Label Edge router, the MGX 8250 can interface to a multiservice IP+ATM network consisting of BPX and/or MGX 8250 Label switches. The MGX 8250 can also interface to a pure IP backbone such as the one depicted in Figure 1-3.
At the edge of the network, the MGX 8250 can interwork with and consolidate a wide variety of CPE equipment (see Figure 1-4): ATM, FR, and voice (both Cisco and multivendor).
Cisco's ability to provide the combination of end-to-end management applications (CiscoView) for all platforms, end-to-end service activation (WAN Service Agent), and value-added Cisco IOS features, allows service providers to focus their training and operations on a single vendor for all services.
The MGX 8250 can be deployed as a stand-alone concentrator, interfacing to a multivendor ATM (non-BPX) network, as shown Figure 1-5. The MGX 8250 interfaces to ATM equipment using a standard ATM UNI or NNI.
The MGX 8250 supports ATM UNI and NNI service for PVCs. The switch can be deployed in scenarios where other ATM equipment has already been deployed and where an MGX 8250 switch can provide a front end as a multiservice concentration device.
The ATM UNI port can be supported at the PXM uplink to eliminate the need to use a separate card for ATM trunking. In addition, the MGX 8250 supports local switching between service modules and PXM ports.
Posted: Mon Oct 2 17:00:33 PDT 2000
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