Apple’s facetime protocol

1. The Technology Behind Apple’s FaceTime Protocol

2. Facetime Facetime is a 2-way video chat service for iPhone 4, iPod touch, iPad 2 and OSX Mac client. Wi-Fi only support. Closed services built on Open Standards.

3. Facetime Call Call initiation requires no ‘registration ’. Facetime registers phone numbers to the phones via apple proprietary methods (non-sip, fully encrypted) Call start using Apple Push Notification Server . SIP used for negotiation and call setup, HTTP and TLS for authentication. RTP and H264&AAC used for media streaming.

4. H264 -Most common video standard today AVC (advanced video coding) SVC (scalable video coding )

5. AAC - Advanced Audio Coding standard Widely used today in audio and video communications, has established interoperability. Commonly used by Apple’s devices.

6. SIP Session Initiation Protocol de-facto standard of IP Communications solutions +Voice and video Used by majority of video conferencing vendors: Cisco, Tandberg, Polycom , RADVISION and more. One of the core standards in 3GPP IMS

7. STUN, TURN and ICE Used together to support Firewall and NAT traversal functionality STUN- allows to map internal IP addressed behind the NAT to the external IP addresses TURN- used in rare cases where STUN doesn’t provide a solution ICE- umbrella standard utilizing STUN, TURN, uPnP in order to find ways to transfer the NAT and Firewall.

8. RTP Real-time Transport Protocol: Voice and Video over IP implementations carrying over real-time media and collecting of the statistics Jitter+latency , which allows to implement better quality solutions. Used by absolute majority IP voice and video vendors.

9. SRTP Secure RTP profile for secure RTP communication Encryption Message authentication Integrity Used in both IP Video and Voice implementations