The Cisco CSS 11500 with the award-winning Cisco Web Network Services (WebNS) is a compact modular platform specifically designed to provide robust transport and application (Layer 4-7) services for Internet and intranet data centers. The Cisco CSS 11500 Series Content Services Switch enables businesses to simultaneously reduce costs by optimizing data center resources and boost productivity by offering a superior online experience for customers, business partners, and employees. Through fast switching and forwarding of content, the Cisco CSS 11500 Series switches improve utilization, responsiveness, availability, scalability, and security of Web sites, server farms, cache clusters, and firewall systems.The Cisco CSS 11500 Series Content Services Switch includes two models: the two-rack unit, three-slot Cisco CSS 11503 with 20-Gbps aggregate throughput and the five-rack unit, six-slot Cisco CSS 11506 with 40-Gbps aggregate throughput. The modules, memory and disks for the Cisco CSS 11506 are interchangeable with those for the Cisco CSS 11503.