The Cisco 10000 ESR dedicates two slots for active and redundant processor modules and eight slots for interface modules. Interface modules can be configured in any of the eight available slots.
All modules require a single slot and are hot-swappable.
Two PREs can be con- figured in a single chassis for redundancy. The design of the backplane that interconnects circuit boards in a router is critical to longevity of the product and the degree of investment protection that can be provided over the lifetime of the device. The Cisco 10000 ESR backplane was designed with future growth in mind. Most communications devices are based on a shared system bus to which all circuit cards are attached. Buses with many loads often suffer electrical reflections and signal degradation that cannot be corrected by improved semiconductor technology.