Symptom:

Users complain abut slow video and audio streams when scanning through ProxyAV

Problem:

Need to effective use ProxyAV for scanning risky content, while avoiding the scanning of long-lived streaming media files which might impair user experience of video and audio streams.

Solution:

Blue Coat publishes “best practices” for effectively using the ProxyAV for scanning risky content, while avoiding the scanning of long-lived streaming media files which might impair user experience of video and audio streams.

The ProxyAV best practices are available at https://bto.bluecoat.com/doc/10766, specifically section 9, Configuration Best Practices.  I cannot attach the entire PDF here, it is 17MB.

The best practices recommend the following settings:

ICTM:
Select Advanced > Intelligent Connection Traffic Monitoring.
Enable the Intelligent Connection Traffic Monitoring (ICTM) checkbox.

No-scan policy:
Download sample CPL from http://techlabs.bluecoat.com/policy/icap_noscan.txt
Save the file to your desktop, then use a text editor to modify the policy to fit your requirements, and save to the clipboard

To install the policy, Select Configuration > Policy > Policy Files.
Then choose “Install Local File” from drop-down list, select Text Editor.

Scroll to the bottom of the editor window, then paste the contents of your file at the end of the local policy file.
Click Install. A dialog displays, informing you whether the installation was successful.
If necessary, correct any errors in the file and reinstall it.