Explanation
According to the Citrix Virtual Apps and Desktops 7 Deployment and Administration (CWS-215) course, the Citrix ADC can optimize the responses by using HTTP protocol for the services and SSL protocol for the virtual server. This configuration allows the Citrix ADC to terminate the SSL connection from the client and then communicate with the server using HTTP. This way, the data is encrypted between the client and the Citrix ADC, and the Citrix ADC can perform optimization tasks such as compression and caching1: Page 95, Module 5: Citrix Gateway and Citrix StoreFront Integration.