Inside Cisco IOS Software Architecture (CCIE Professional Development)

Hardware Architecture for Shared Memory Routers

Let's examine the hardware architecture on these shared memory platforms in some detail. We start with an overview of the generic shared memory architecture in Figure 3-1, and then mention some of the unique hardware features of platforms within this group.

You can see the overall architecture is fairly basic, consisting of just three major components: the processor (CPU), memory (DRAM), and interface controllers, with the processor and the interface controllers connected to the memory via data busses. Figure 3-1 also shows memory is divided into logical regions, which we'll examine later.

Figure 3-1. Shared Memory Router Architecture

CPU

The processor in a shared memory router is truly