If you haven't already heard about WebRTC, it is one of the hottest buzz words around town (early 2014). WebRTC is an emerging standard that
enables a browser-to-browser voice, video and data sharing without the need of
plugins, software or centralized communication infrastructure. It is an
innovative technology that finds many applications, ranging from simply sharing
a URL to start a video-conference between two browsers to buyers looking at the
products in real-time as apposed to static images before they complete the purchase.
The WebRTC
has the potential to impact businesses including PBX firms, videos firms and
web conferencing firms.
Here is my brief summary of
WebRTC technology with an emphasis technologies that enable WebRTC on Apple
iOS devices.
Technology Overview
The WebRTC is a communications standard developed by the W3C
in close cooperation with the RTCWeb standard developed by the IETF. In
practice WebRTC is a set of Libraries/Application
Programming interfaces (API) designed to allow Real Time Communication (RTC)
using web-browsers without requiring plugins, downloads or
installs. The WebRTC is a part of HTML 5 that offers web application
developers the ability to write rich, real-time multimedia applications on the
web using simple JavaScript APIs and HTML.
Background
Google Inc. started WebRTC as a royalty free
project. The WebRTC standard solves a common problem for video communication
in today’s trends 1). Incompatibilities for real-time communications, with
a goal to build a standards-based real time media engine implemented in all of
the available browsers, 2). WebRTC
leverages the recent trend in which the web browser is the main
“application-runtime”.
Figure 1,
WebRTC enabled browsers communicating with different Applications [1].
A WebRTC enabled browser can leverage any
signalling system through a web-service that can direct the browser to
establish a voice or video RTP connection to another WebRTC enabled device or
media server. Once the initial connection is established the WebRTC APIs and
the media engine defines and controls the communications path.
To achieve fully immersive video-calling solution WebRTC
API standard can be split in to two layers.
The web application layer
Much of the promise of WebRTC is in the fact that it
provides APIs from the browser to the underlying hardware. The web-application
developers can communicate with the WebRTC API by calling a set of simplified JavaScript
methods. The programming methods are directed to the driver interfaces that provide
controls to underlying microphones, and video capture hardware etc.
With WebRTC enabled in a browser (both mobile and
desktop), developers can:
· Capture camera or
microphone streams directly from a browser using only JavaScript.
· Make browser-to-browser
calls (audio and/or video).
· Share data (no server in
the middle) to enable peer-to-peer apps (e.g. text chat, gaming, image sharing
especially during calls)
The Browser Layer
To implement the code that will allow web browser engines to
respond to the JavaScript API calls; A WebRTC stack is also available as a C++ API that allows
browsers to capture and hook hardware resource at their disposal.
Figure 2, WebRTC application stack [2]
WebRTC
support in desktop browsers
·
For
the PC, the WebRTC is currently built into the latest Google Chrome version 32.0.0,
Opera 18+, Firefox version 27.0, and Internet Explorer using a WebRTC
compatible CU-RTC-Web API, a Microsoft implementation of WebRTC like library
[3].
·
For
Linux based desktops WebRTC is available in the current Chromium version 29.0.0
(beta) Chrome 31.0.0 and Firefox 27.0.
·
For
Apple Mac, the native browser Safari does not support WebRTC. The WebRTC
support is available through the latest Google Chrome, Firefox and Opera 18+, but
none of the browser’s supports 100% of the WebRTC API functions. A current
implementation status WebRTC functions can be viewed in Figure.3.
Figure 3,
current status of WebRTC functions implemented [2][4].
Other than the browser base support on the Mac, there
are also few bespoke implementations of WebRTC available for Apple Macs e.g.
TenHands, a startup video conferencing company, has embedded their WebRTC
capability into FaceTime. The Vidtel is another a cloud based video bridge
provider and has already incorporated the WebRTC stack in their Mac SDK.
1
WebRTC
on Mobile Platforms
1.1
Android
Both Google
chrome and Mozilla Firefox browsers are fully supported on android platform.
Firefox WebRTC support is in its infancy and it has few bugs running a full
WebRTC session; such as, issues with echo cancellation, CPU overutilization and
video frame occasional out of sync issues [5, 6, 7].
1.2
Apple iOS
Apple iOS
is the 2nd most used mobile platform with millions of people using
iOS devices. Apple’s take on web browsers for iOS devices is different
than other platform. Apple's
development agreement makes sure that only iOS’s default browser Safari can be
used as a backend engine for any browser running on iOS. Google Chrome is available for iOS devices but
it’s restricted from using the Google’s latest WebKit or Blink rendering
engine. A Google-Chrome running on an iOS
device does not use the V8 JavaScript engine and it does not have a
multi-process architecture. The iOS limitations make sure that all third-party
browsers are built using UIWebView, so they use the same rendering and
JavaScript engine. Among other issues such as Safari’s browser engine is slower
than the competition it also does not support WebRTC without any apparent
roadmap to support it.
While
reviewing the limitations of browsers on iOS it should also be kept in mind
that consumption on smartphones especially iOS takes place more using dedicated
apps than in the web-browser.
Following
are the few vendors that implement WebRTC either as a dedicated app or plugin
for WebRTC.
1.2.1 Bowser
Bowser is an experimental implementation of WebRTC on iOS
and Android, developed by Ericsson Research [8]. Bowser is not only an App but
also a dedicated WebRTC-enabled browser for mobile devices. ‘Bowser’ web
browser is based on an Open Source project called the "WebRTC3”, which is
being developed within the World Wide Web Consortium and the Internet
Engineering Task Force (IETF).
1.2.2 Bistri
Bistri is a
simplified one-link solution to enable mobile communication between web
browsers by sharing a URL, which can be sent in an email or shared using an IM.
Its based on WebRTC technology and it has their service available for web, iOS
and Android [9].
1.2.3 TokBox
TokBox provides
hosted cloud infrastructure, APIs and pre-configured tools required to deliver
enterprise-grade WebRTC capabilities. It does so primarily through its
proprietary OpenTok video platform for commercial application. The latest
version of OpenTok 2.0 iOS SDK allows OpenTok based WebRTC video sessions in
apps built for iPad, iPhone, and iPod touch devices.
Telefonica recently
acquired TokBox. The majority of the customer base for TokBox is with vendors
who have used their services to add an interactive layer of interface to personalize
interaction with their online customers, using just a web-browser [10].
1.2.4 AddLive
AddLive is another simple SDK that can be used to integrate
live video, voice and text chat into applications using WebRTC ecosystem. The
AddLive SDK support both iOS and Android.
1.2.5 Voxeo
Voxeo
Corporation is a telecommunication company that specializes in providing
development platforms for unified customer experience (self-service) and
unified communications (real time communications) applications. Voxeo has a proprietary
SDK for iOS called Phono. The Phono ‘Cordova’ plugin adds the power of Phono
[11] to mobile app using the PhoneGap application framework for iOS devices.
1.2.6 Twilio
Twilio Mobile
SDK for iOS and Android has used WebRTC to deliver an Internet base
telecommunication service. Working on a on a marketing pitch of making any
device a phone, they provide local phone numbers with SMS and video/voice call
facility in over 17 countries [12].
To provide
WebRTC integration Twilio has developed a very stable SDK called Twilio-Cliet. Twilio-Client
iOS is an Objective-C library for iOS that enables voice communications with
landlines or other Twilio Client devices, including web browsers and other
mobile devices.
1.2.7 OpenClove
OpenClove is a mobile
tech company that delivers cloud-based mobile and video communication platform.
OpenClove online video exchange (OVX) is
the first cloud based video MRF with WebRTC support enabling video in any web
or mobile application. OpenClove’s video cloud platform is complete with APIs
has not only an SDK for iOS (and Android) [14] but also an established app of
their own, called ‘LiveBoard’.
1.2.8 Hookflash
Hookflash
is another cloud based voice communication solution. It provides an RTC toolkit
that comes with WebRTC enabled SDKs for iOS, Android and now Blackberry 10. It
also has an implementation for P2P signaling protocol that allows WebRTC to
setup an complete PBX integration without a centralized server [15].
1.2.9 EasyRTC
EasyRTC
is the only full-stack open source WebRTC Solution. It comprises of a toolkit
suitable for building secure, enterprise WebRTC applications. The SDK provides
a bundle of web applications, code snippets, client libraries and server
components meticulously written and documented to work right out of box [16].
·
[16]
- http://www.easyrtc.com
