You may have an option on your Firewall to enable or disable RTSP Transformations, but what are they and should you disable or enable them?

RTSP or Real Time Streaming Protocol is detailed in RFC2326 (http://www.ietf.org/rfc/rfc2326.txt) and is an application-level protocol for dealing with real time streaming of information such as video, high resolution images or audio feeds.

Streaming data can consume large amounts of bandwidth so are often served by proxy servers which distribute the load from the master servers. These proxy servers may transform the data stream they receive to optimise performance – this may involve changing the format or compressing the information in some way. By transforming the data it could be possible for some information to be lost, and the additional processing overhead could introduce some delay.

If you require real-time data to reach you without being transformed (the example given in the RFC is that a medical image must not be interfered with) then you should not allow RTSP transformations to take place; the streaming application must support the RTSP for this option to apply (the application server can also specifically specify proxy servers must not transform the stream).