Avaya M770 14

Chapter 2	Introduction

Architecture

The Avaya M770 hub features distributed processing on each of the modules, so there is no single point of failure. Most of the switching takes place on the module itself; only when a packet must travel from one module to another does it traverse the backplane. It is this combination of module and backplane switching that enables the Avaya M770 to deliver aggregate bandwidth of over 80 Gbps.

The Avaya M770 Multiswitching Backplane

The Avaya M770 architecture enables you to use whichever mix of switching technologies you require.

The Avaya M770 hub has multiple modular backplanes, allowing connection of Frame switch, Cell switch, and Avaya M440 Gate Switch modules.

The lower section of the backplane is dedicated to frame switching and supports two frame switches, called DomainXs. Frame Switch modules can be inserted into either of the DomainXs - DomainXL in the left half of the hub (slots 1-7), DomainXR in the right half of the hub (slots 8-14).

The upper backplane supports two switches called DomainGs, currently used for cell switching. Cell switch modules can be inserted into either of the DomainGs - DomainGL in the left half of the hub, DomainGR in the right half of the hub.

Although the upper backplane is currently utilized for ATM cell transfer, its bus architecture is open, and can be easily adapted to support new technologies as they emerge.

The lower section of the backplane also includes the High Speed bus for Avaya M440 modules and their agent modules. Since these modules are 6U high, an adapter bracket is required for their insertion (see Chapter 5).

Figure 2.2 Avaya M770 Backplane Architecture

Multiple Resilient Switching Domains