The Versatile Interface Processor 4 (VIP4) for the high-end Cisco 7500 router series enables high-performance switching, and scalable LAN and WAN intelligent network services to meet the needs of high-performance applications. It provides over twice the distributed switching performance and twice the aggregate bandwidth of previous model VIPs, employs higher-capacity memory modules for rich IP services, and utilizes Error Correction Code (ECC) for increased system availability. The VIP4 serves as an ideal platform for enterprise and service-provider networks that require high performance and processing power to support service-enabled edge and core applications.There are two different versions of the VIP4: the VIP4-80 and the VIP4-50, providing two levels of distributed switching and services performance, matching system performance requirements to overall deployment costs. Both VIP4 versions support two modular PAs and identical ECC-protected memory expansion options. The VIP4-50 offers support for distributed switching and distributed services. Powered by a 250-MHz RM5000 microprocessor, it provides large program memory to accommodate Layer 3-route information from the RSP for autonomous switching decisions, and large packet memory capacity necessary for distributed IP services. In addition, the VIP4-50 runs a subset of Cisco IOS software to provide support for enhanced network services such as distributed queuing and software-based encryption and compression.