Measuring Performance Overhead of Trans-encrypting HTTP Adaptive Streaming

The content distributors take content protection and Digital Rights Management of content very serious. As such many provisions already exist to make sure content is securely sent to, and only to, licensed clients. In this paper an alternative content encryption system is proposed by using the homomorphic features of asymmetric cryptography systems. Using a split-key derivative of the RSA cryptosystem, representing asymmetric split-key cryptography, the overhead of doing a trans-encryption operation on an edge was evaluated. The results show that using the split-key RSA cryptosystem degrades performance significantly over using a similar AES128 re-encrypting cryptosystem but show area for improvement. Although the split-key RSA cryptosystem doesn’t perform satisfactory it does provide the ability to distribute over untrusted third-party Content Delivery Networks (CDNs) as content is never decrypted along the pipeline, where this is the case for the similar AES-128 cryptosystem.