The Cisco Cache Engine 500 series products accelerate content delivery, optimize WAN bandwidth utilization, and control access to content.Rapid increases in network traffic have created numerous networking challenges for Internet service providers (ISPs) and enterprises, including: WAN bandwidth congestion and high transmission costs, maximizing and controlling the network service quality, maximizing availability of Internet and intranet content as seen by clients, cost-efficient network scalability. The most efficient solution to these networking problems is to use your existing network infrastructure to localize traffic patterns, enabling content requests to be fulfilled locally. Therefore, the first step in building a traffic localization solution is to ensure that your existing network supports traffic localization. This capability can be achieved by enabling content routing technology, such as software's Web Cache Communication Protocol (WCCP), at key points within your network. Once the right network foundation is in place, network caches are added into strategic points within your existing network to complete the traffic localization solution. Network caches transparently cache or store frequently accessed content and then locally fulfill successive requests for the same content, eliminating repetitive transmission of identical content over WAN links. Thus, the complete caching solution is comprised of a networking component and a cache component.