An administrator configures a Cisco WSA to receive redirected traffic over ports 80 and 443.

Transparent traffic redirection using WCCP is a deployment mode for the Cisco WSA that allows it to intercept and proxy web requests from client applications without requiring any configuration on the clients. This mode increases the visibility and control of web traffic, while making the proxy function invisible to the users. To support this mode, the Cisco WSA must be configured to use the transparent proxy mode, which enables it to listen on ports 80 and 443 for HTTP and HTTPS traffic, respectively. The Cisco WSA must also be configured to use WCCP service IDs, which are numerical identifiers that specify the type and range of ports to be redirected. For example, service ID 0 (web-cache) redirects port 80, service ID 70 (https-cache) redirects port 443, and service ID 60 (ftp-native) redirects port 21 and a range of passive FTP ports. The Cisco WSA must also be configured to join a WCCP group, which is a set of WCCP routers or switches that cooperate to redirect traffic to the WSA. The WCCP group can be specified by a group list, which is an access list that defines the IP addresses of the WCCP routers or switches, or by a password, which is a shared secret that authenticates the WCCP communication. The WCCP group must also be configured on the network device that performs the traffic redirection, such as a Cisco router, switch, or ASA firewall. The network device must support WCCPv2, which is the latest version of the protocol that allows for advanced features such as load balancing, encryption, and GRE encapsulation. The network device must also be configured to use the same WCCP service IDs and group list or password as the Cisco WSA. The network device must also be configured to apply the WCCP redirection to the appropriate interface and direction, such as the inside interface and inbound direction for traffic originating from the internal network. The network device must also be configured to use an access list that defines the traffic to be redirected or bypassed, such as the source and destination IP addresses, ports, and protocols. The access list can also be used to exclude certain traffic from WCCP redirection, such as traffic to private or internal destinations, or traffic from specific hosts123 References := 1: Configure Transparent Redirection With WCCP in Order to Redirect Native FTP Traffic - Cisco 2: Solved: Transparent Redirection - Cisco Community 3: Cisco WSA : Is it possible to use web proxy in transparent mode without WCCP - Cisco Community