Existing Cache Deployment

This option allows the web appliance to work in conjunction with an existing web-caching server.


The operation will vary according to the deployment scenario that you choose. As an example, the deployment shown in the diagram above and described in the points below is based on a Bridged Deployment.

  • Users’ URL requests are passed to the web appliance .
  • The web appliance passes allowed requests to the cache server .
  • If the cache server does not have the pages or files cached, it passes the request through the firewall ; if it has the requested pages or files cached or when the request is returned through the firewall, the cache server passes the requested pages or files back to the web appliance .
    Note Even with the presence of a cache server, the web appliance will cache static content.
    Note This configuration is not intended to work with Microsoft Internet Security and Acceleration (ISA) servers or Microsoft Forefront Threat Management Gateway (TMG) servers. If you want a network deployment that will work effectively with ISA/TMG servers, try either the Downstream ISA/TMG Server Deployment or the Upstream ISA/TMG Server Deployment.
  • The web appliance scans the pages or files and passes allowed requests back to the users .
  • The users receive only safe and allowed pages and file or a notification page.


Follow the configuration instructions for the basic network deployment scenario that you want to use (Explicit Deployment, Transparent Deployment, or Bridged Deployment), but with the following differences:

  • Ensure that your existing cache server is between your web appliance and your firewall.
  • Ensure that your cache server is configured to be transparent to the web appliance.