Disclosed herein are systems and techniques for content protection over synchronous data networks. For example, a method of communicating content protected data may include providing link synchronization information over a link of a synchronous bus, and providing content protected data over the link of the synchronous bus. The content protected data may be protected in accordance with the High-Bandwidth Digital Content Protection (HDCP) specification or the Digital Transmission Content Protection (DTCP) specification, for example.