Scenario: virus checking in an enterprise

About this scenario

This scenario describes how an ICAP server running virus checking software checks an executable file that an origin server is returning in response to a client request.

Organization's requirements

LMN, Incorporated, an enterprise, has the following goals:

Reduce bandwidth consumption by caching HTTP objects and objects requested through HTTP
LMN wants to cache downloadable files, such as PDF files, to reduce the amount of bandwidth that results when multiple clients request the same downloadable files.
Add a virus checking service to prevent viruses from being downloaded to the network
LMN cannot trust each origin server to provide virus-free data. The reason is that origin servers might have been compromised and virus-infected files might be installed.

Deployment illustrated

The deployment for LMN is shown in the following illustration.

As the previous illustration shows, when a user sends a request to download an executable file, the NetCache ICAP client passes the file it receives from the origin server to the ICAP server for virus checking before caching the file.