What is TLS/SRTP?

Transport Layer Security (TLS) and Secure Real-time Transport Protocol (SRTP) are two technologies which together help secure online communications. 


Ever seen the padlock icon on your browser when visiting a secure site? Then you’ve visited a TLS-protected website. 

TLS is a cryptographic security protocol for encrypting Voice over Internet Protocol (VoIP) calls. It’s an evolution of the Security Sockets Layer (SSL). 


What about SRTP? SRTP is an extension of RTP, a real-time transport protocol for delivering audio and video over an IP network. SRTP adds a layer of encryption, confidentiality assurance, and message authentication to protect webRTC conversations. 

SRTP is invaluable in VoIP applications for preventing security breaches and denial-of-service (DoS) attacks without significantly impacting the quality of service.  

What are the benefits of TLS/SRTP? 

Both TLS and SRTP provide a more secure and private experience. How? TLS encrypts the signaling portion of the call, while SRTP secures the actual VoIP data. A combination of the two provides strong security, especially if you’re using a softphone on a public network. 

Here’s what you need to know: 

  • TLS adds an extra layer of security in the form of certificates: A certificate authority must authenticate these certificates before granting access to an entity in a communication network. However, TLS does not protect data at rest. It only prevents eavesdropping while the data packets are in transit from a sender to a recipient machine. 
  • SRTP ensures no one has tampered with the data packets in the exchange: SRTP can validate messages to prevent man-in-the-middle attacks. It also verifies the recipient’s identity and keeps your messages encrypted so no one can intercept or eavesdrop on your conversations. 
  • SRTP supports various encryption libraries to stay secure: It runs with low computational cost and can still function despite restricted bandwidth. 

How does Sinch work with TLS/SRTP? 

TLS/SRTP work to ensure privacy and security in your communications. This is incredibly important in the digital age where sensitive information is being shared at all times. 

Sinch’s industry-leading network and suite of collaboration tools leverage the latest encryption technologies, including TLS and SRTP to provide a safe and secure user experience.