|By Frank Salim||
|December 16, 2008 10:12 AM EST||
Chat rooms and live peer-to-peer chat on the web are high on the list of stunning rich application features that can still drop jaws. Facebook recently launched an integrated web chat implementation to much fanfare. Their impressive Erlang and C++ chat infrastructure showcases real-time web techniques and live, interactive interface elements. However, following Facebook's lead is actually not that hard if you use the right approach.
The two main difficulties faced by Facebook, Google, or any other web giant that wishes to deploy a chat application are scaling out an inconceivably large messaging back end and sending real-time messages to the browser. The first problem is one that many of us would like to have, but few actually encounter. The second problem is getting much, much easier to solve. Web chat is about to go mainstream, thanks in large part to a new HTML 5 feature called Web Sockets.
Chat Is Full-Duplex; the Web Is Not
The challenges in bringing real-time messaging (chat, for example) to web applications stem from the fundamental design of the web. It is, after all, a system designed for navigating hypertext documents. The request-response model is perfect for document retrieval, but it's less perfect for an application platform. Some applications are exceptionally bad fits.
Chat requires full-duplex communication. That is, data must be able to flow bidirectionally. This is a clear necessity for chat, as messages may originate on either the server or the client and must be transmitted without delay. After all, instant messaging is of little use if it isn't instantaneous. HTTP explicitly eliminates the ability to send information over the network in either direction at will at the same time.
Since nearly anything is possible, some tenacious developers have shoehorned full-duplex communication into existing web browsers. Comet long-polling, iframe streaming, and other techniques have all been applied in pursuit of this goal. Each technique has weaknesses, however, and even Comet techniques that allow data to stream down from the server cannot avoid initiating a new request for each upstream message. While a new request might not seem like much, each HTTP action causes several hundred bytes of header data to be generated, transmitted, and parsed. Even when bandwidth and computing resources are cheap, the additional latency incurred by a full round trip hurts real-time interactivity.
Using today's browser technology for both upstream and downstream, there is significant overhead to real-time communication. Despite this, some have been willing to stomach the complexity and inefficiency to run applications like chat on the web without succumbing to the temptation of proprietary plugins.
HTML 5 Web Sockets
The HTML 5 standard specifies new APIs for storage, drawing, drag-and-drop, and other areas that have made web programming painful. Browsers have already begun incorporating parts of HTML 5 (canvas, for example) even though the specification is far from complete. The HTML 5 Communication section includes two additional connectivity features: Server-Sent Events, a standardization of HTTP push, and Web Sockets, a cross-domain safe, full-duplex connection. Server-Sent Events will make real-time updates and notifications easy, and Web Sockets provide the functionality necessary to build chat for the web without the previously required hackery.
|393rocker 11/02/09 10:02:00 AM EST|
do u have a source code of implementing IM? if i start from the scratch..
SYS-CON Events announced today that AIC, a leading provider of OEM/ODM server and storage solutions, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. AIC is a leading provider of both standard OTS, off-the-shelf, and OEM/ODM server and storage solutions. With expert in-house design capabilities, validation, manufacturing and production, AIC's broad selection of products are highly flexible and are conf...
Dec. 21, 2014 06:30 AM EST Reads: 1,917
ARMONK, N.Y., Nov. 20, 2014 /PRNewswire/ -- IBM (NYSE: IBM) today announced that it is bringing a greater level of control, security and flexibility to cloud-based application development and delivery with a single-tenant version of Bluemix, IBM's
The BPM world is going through some evolution or changes where traditional business process management solutions really have nowhere to go in terms of development of the road map. In this demo at 15th Cloud Expo, Kyle Hansen, Director of Professional Services at AgilePoint, shows AgilePoint’s unique approach to dealing with this market circumstance by developing a rapid application composition or development framework.
Dec. 20, 2014 11:00 PM EST Reads: 1,310
SYS-CON Events announced today Isomorphic Software, the global leader in high-end, web-based business applications, will exhibit at SYS-CON's DevOps Summit 2015 New York, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Isomorphic Software is the global leader in high-end, web-based business applications. We develop, market, and support the SmartClient & Smart GWT HTML5/Ajax platform, combining the productivity and performance of traditional desktop software ...
Dec. 20, 2014 11:00 PM EST Reads: 1,206
"BSQUARE is in the business of selling software solutions for smart connected devices. It's obvious that IoT has moved from being a technology to being a fundamental part of business, and in the last 18 months people have said let's figure out how to do it and let's put some focus on it, " explained Dave Wagstaff, VP & Chief Architect, at BSQUARE Corporation, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 20, 2014 12:00 PM EST Reads: 1,961
The major cloud platforms defy a simple, side-by-side analysis. Each of the major IaaS public-cloud platforms offers their own unique strengths and functionality. Options for on-site private cloud are diverse as well, and must be designed and deployed while taking existing legacy architecture and infrastructure into account. Then the reality is that most enterprises are embarking on a hybrid cloud strategy and programs. In this Power Panel at 15th Cloud Expo (http://www.CloudComputingExpo.com...
Dec. 20, 2014 11:30 AM EST Reads: 2,391
"Our premise is Docker is not enough. That's not a bad thing - we actually love Docker. At ActiveState all our products are based on open source technology and Docker is an up-and-coming piece of open source technology," explained Bart Copeland, President & CEO of ActiveState Software, in this SYS-CON.tv interview at DevOps Summit at Cloud Expo®, held Nov 4-6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 20, 2014 11:00 AM EST Reads: 1,980
The Internet of Things is not new. Historically, smart businesses have used its basic concept of leveraging data to drive better decision making and have capitalized on those insights to realize additional revenue opportunities. So, what has changed to make the Internet of Things one of the hottest topics in tech? In his session at @ThingsExpo, Chris Gray, Director, Embedded and Internet of Things, discussed the underlying factors that are driving the economics of intelligent systems. Discover ...
Dec. 20, 2014 11:00 AM EST Reads: 2,300
SYS-CON Events announced today that Windstream, a leading provider of advanced network and cloud communications, has been named “Silver Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. Windstream (Nasdaq: WIN), a FORTUNE 500 and S&P 500 company, is a leading provider of advanced network communications, including cloud computing and managed services, to businesses nationwide. The company also offers broadband, p...
Dec. 20, 2014 10:45 AM EST Reads: 2,246
SYS-CON Media announced today that Aruna Ravichandran, VP of Marketing, Application Performance Management and DevOps at CA Technologies, has joined DevOps Journal’s authors. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. DevOps Journal brings valuable information to DevOps professionals who are transforming the way enterprise IT is done. Aruna's inaugural article "Four Essential Cultural Hacks for DevOps Newbies" discusses how to demonstrate the...
Dec. 20, 2014 10:00 AM EST Reads: 1,783
The move in recent years to cloud computing services and architectures has added significant pace to the application development and deployment environment. When enterprise IT can spin up large computing instances in just minutes, developers can also design and deploy in small time frames that were unimaginable a few years ago. The consequent move toward lean, agile, and fast development leads to the need for the development and operations sides to work very closely together. Thus, DevOps become...
Dec. 20, 2014 10:00 AM EST Reads: 2,031
Verizon Enterprise Solutions is simplifying the cloud-purchasing experience for its clients, with the launch of Verizon Cloud Marketplace, a key foundational component of the company's robust ecosystem of enterprise-class technologies. The online storefront will initially feature pre-built cloud-based services from AppDynamics, Hitachi Data Systems, Juniper Networks, PfSense and Tervela. Available globally to enterprises using Verizon Cloud, Verizon Cloud Marketplace provides a one-stop shop fo...
Dec. 20, 2014 09:00 AM EST Reads: 1,965
AppZero has announced that its award-winning application migration software is now fully qualified within the Microsoft Azure Certified program. AppZero has undergone extensive technical evaluation with Microsoft Corp., earning its designation as Microsoft Azure Certified. As a result of AppZero's work with Microsoft, customers are able to easily find, purchase and deploy AppZero from the Azure Marketplace. With just a few clicks, users have an Azure-based solution for moving applications to the...
Dec. 20, 2014 09:00 AM EST Reads: 1,001
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Dec. 20, 2014 08:00 AM EST Reads: 1,327
SYS-CON Events announced today that IDenticard will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. IDenticard™ is the security division of Brady Corp (NYSE: BRC), a $1.5 billion manufacturer of identification products. We have small-company values with the strength and stability of a major corporation. IDenticard offers local sales, support and service to our customers across the United States and Canada...
Dec. 20, 2014 07:00 AM EST Reads: 2,132