WebRTC

WebRTC (Web Real-Time Communication) is an API definition drafted by the World Wide Web Consortium (W3C) that supports browser-to-browser applications for voice calling, video chat, and P2P file sharing without the need of either internal or external plugins.^[1]

History

In May 2011, Google released an open source project for browser-based real-time communication known as WebRTC.^[2] This has been followed by ongoing work to standardise the relevant protocols in the IETF^[3] and browser APIs in the W3C.^[4]

The W3C draft of WebRTC^[5] is a work in progress with advanced implementations in the Chrome and Firefox browsers. The API is based on preliminary work done in the WHATWG.^[6] It was referred to as the ConnectionPeer API, and a pre-standards concept implementation was created at Ericsson Labs.^[7] The Web Real-Time Communications Working Group expects this specification to evolve significantly based on:

• Outcomes of ongoing exchanges in the companion RTCWEB group at IETF^[8] to define the set of protocols that, together with this document, define real-time communications in Web browsers. While no one signalling protocol is mandated, SIP over Websockets (RFC 7118) is often used partially due to the applicability of SIP to most of the envisaged communication scenarios as well as the availability of open source software such as JsSIP.
• Privacy issues that arise when exposing local capabilities and local streams
• Technical discussions within the group, on implementing data channels in particular^[9]
• Experience gained through early experimentation
• Feedback from other groups and individuals

Design

Major components of WebRTC include:

• getUserMedia, which allows a web browser to access the camera and microphone and to capture media^[10]
• RTCPeerConnection, which sets up audio/video calls^[11]
• RTCDataChannel, which allow browsers to share data via peer-to-peer^[12]

The WebRTC API also includes a statistics function:

• getStats, which allows the web application to retrieve a set of statistics about WebRTC sessions. These statistics data are being described in a separate W3C document.^[13]

As of March 2015, the IETF WebRTC Codec and Media Processing Requirements draft^[14] requires implementations to provide PCMA/PCMU (RFC 3551), Telephone Event as DTMF (RFC 4733), and Opus (RFC 6716) audio codecs, along with the H.264 and VP8 video codecs as minimum capabilities. The Peerconnection, Data channels and a media capture browser APIs are detailed in the W3C.

W3C is developing ORTC (Object Real-time Communications) for WebRTC.^[15] This is commonly referred to as WebRTC 1.1.

Benefits

WebRTC enables all kinds of real time communication such as audio, video and text between users by utilising the browsers. Using WebRTC bears different benefits for different market segments. For end users it has two major advantages:

• Ease of use: Real-time communication is supported without the need for additional applications or plug-ins.
• Security: WebRTC enforces the usage of encryption for both the media and the signalling. Thereby, WebRTC provides a higher security level than most currently available commercial telephony systems.

For enterprises WebRTC can provide even more benefits:^[16]

• Cost savings:
  • Save on the costs of toll-free telephone number for call centres
  • Reduce the costs of using VPN to connect home offices and remote branches.
• Rich communication: Enhance the communication to users and between employers with video and messaging without the need for special applications and servers.
• Un-interrupted communication: Keep the customers on the web page and at the same time start a voice and video call with customer.
• Security: Secure the communication with the customers as well as employees in the home office and remote branches using state of the art encryption standards.

For operators, WebRTC can additionally provide new opportunities:

• Mobile Telephony: By relying on WebRTC technology, service providers can enable users to access their VoIP service while on the go without specialised applications.
• Hosted Services: By deploying a WebRTC gateway end users would be able to access the SIP based hosted PBX and call centers without the need to change these services.
• WebRTC as a Service: Similar to hosted PBX services, service providers can host WebRTC Gateways on behalf of enterprises. WebRTC calls destined to the enterprise are handled by a WebRTC Gateway of the service provider. Incoming WebRTC calls would be translated into SIP calls and routed to the enterprise. The enterprise would not have to change anything in its infrastructure, as it will still be only handling SIP calls

Concerns

In January 2015, TorrentFreak reported that browsers supporting WebRTC suffer from a serious security flaw that compromises the security of VPN-tunnels, by allowing the true IP address of the user to be read.^[17] The IP address read requests are not visible in the browsers developer console, and they are not blocked by common ad blocking/privacy plugins (enabling online tracking by advertisers and other entities despite precautions).^[18]

Support

WebRTC is supported in the following browsers.

• Desktop PC
  • Google Chrome 23
  • Mozilla Firefox 22^[19]
  • Opera 18^[20]
• Android
  • Google Chrome 28 (Enabled by default since 29)
  • Mozilla Firefox 24^[21]
  • Opera Mobile 12
• Chrome OS
• Firefox OS
• iOS
  • Bowser^[22]

As of August 2014, Internet Explorer and Safari still lack the native support of WebRTC.^[23] Several plugins are available to add the support of WebRTC to these browsers.^[24][25]

Disabling WebRTC

WebRTC can be enabled and disabled in Firefox by toggling the value of "media.peerconnection.enabled" in about:config, and WebRTC settings can be changed in about:webrtc.

WebRTC cannot be disabled in the desktop version of Google Chrome. ^[26]

See also

• CU-RTC-WEB
• Jingle (protocol)
• Datagram Transport Layer Security (DTLS), Secure Real-time Transport Protocol (SRTP) - DTLS-SRTP is an essential protocol for WebRTC key management

References

External links

• Official website
• W3C Web Real-Time Communications Working Group
• IETF Real-Time Communication in WEB-browsers (rtcweb) Working Group
• Getting Started With WebRTC
• WebRTC Interest and History
• WebRTC:How an Why?