Hardware Architecture of the Cisco 7500 Router

Figure 6-1 provides a high-level diagram of the 7500 router architecture. As you can see from this diagram, there are two components central to understanding the unique features of IOS on the 7500: the data bus and Route Switch Processor (RSP).

Figure 6-1. The 7500 Architecture

The Data Bus

The data bus in the 7500 router, like that of its predecessors (the AGS+ and 7000), is based on the proprietary Cbus architecture.The Cbus used in the 7500 is a faster version of the 7000's Cbus called the CyBus (the 7000's Cbus is often called the CxBus). Like the original Cbus, the CyBus is a 32-bit bus ...

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