Cisco Systems manual Standards-Based Conversion to ATM, MGX 8230 Enclosure and Power

Chapter 1 Introducing the MGX 8230

MGX 8230 System Overview

The supported interfaces for user-traffic are:

•Frame Relay UNI on T3, E3, HSSI, T1, and E1 lines.

•ATM UNI and FUNI interfaces.

•Optional inverse multiplexing for ATM (IMA).

•Frame Relay to ATM network interworking and service interworking.

•Circuit Emulation services for T1/E1 and T3/E3 lines.

The optional Service Resource Module-3T3 (MGX-SRM-3T3/C) can support up to 64 T1 interfaces. The MGX-SRM-3T3/C can also provide 1:N redundancy for the T1 and E1 line cards.

The modular, software-based system architecture enables the 8230 to support new features through downloadable software upgrades or new hardware modules.

The MGX 8230 backplane supports individual line rates range from DS0 through OC-3.

Standards-Based Conversion to ATM

The MGX 8230 converts all user information into 53-byte ATM cells by using the appropriate ATM Adaptation Layer (AAL) for transport over the ATM backbone network. The individual service modules segment and reassemble (SAR) cells to eliminate system bottlenecks. The following list shows the applicable AAL for each service:

•Circuit emulation services uses AAL1.

•Frame Relay-to-ATM network interworking uses AAL5 and Frame Relay Service Specific Convergence Sub-layer (FR-SSCS).

•Frame Relay-to-ATM service interworking uses both transparent and translation modes to map Frame Relay to native ATM AAL5.

•Frame Forwarding uses AAL5.

MGX 8230 Enclosure and Power

The MGX 8230 has a 14 single-height slot (7 double-height) chassis. This chassis can be rack mounted in a 19-inch rack, or fitted with side panels to be a free-standing box (referred to as a “stand-alone” MGX 8230). An optional mounting bracket kit is also available for mounting the MGX 8230 in 23-inch racks.

Note Although the card slots in an MGX 8230 are horizontal, this manual refers to the card slots and modules as single-height and double-height. This is for consistency: the PXM1 core card and service module cards are a subset of the MGX 8250 cards that are installed vertically in an MGX 8250 chassis.

Slot Numbering and Placement

The MGX 8230 slots are populated with cards and modules according to the following rules (Figure 1-2):

•The slots are numbered 1 to 7 on the left half of the chassis. The slots on the right side of the chassis are numbered 8 to 14.

	Cisco MGX 8230 Edge Concentrator Installation and Configuration
1-4	Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001