The Real-time web is a network web using technologies and practices that enable users to receive information as soon as it is published by its authors, rather than requiring that they or their software check a source periodically for updates.
The real-time web is different from real-time computing in that there is no knowing when, or if, a response will be received. The information types transmitted this way are often short messages, status updates, news alerts, or links to longer documents. The content is often “soft” in that it is based on the social web—people’s opinions, attitudes, thoughts, and interests—as opposed to hard news or facts.
From another point of view, the real-time web consists in making the client interface (or the web side; or the web layer) of a web application, to communicate continuously with the corresponding real-time server, during every user connection. As a fast pic of the client/server model, imagine each client object (each web module of the web GUI of an application) having its object class (which remote-controls the GUI) alive as a sub process (of its user session) in the server environment. In this scenario, the web is considered as the human entrance (interface) to the real-time environment (the [server] core engine which runs applications): at each connected web URL, or Internet real-time zone, corresponds a different “front-end” web application. The real-time server acts as a logic network operating system for the programmable array of applications; handles the array of connected users for each application; attends for connections from real-world appliances and second level real-time servers. Applications behaviours and the intercommunication procedures between online services or applications, online users, and connected devices or appliances, are settled in the corresponding source code of each real-time service written in the real-time-interpreted programming language of the centric server.
As opposite to previous scenario, real-time web is exactly soft real-time computing: the round trip of a data ping-pong signal from the real-time server to the client must take about 1s (max) to be considered real-time and not to be annoying for humans (or users) during their connections. About the dispute between social web and real-time web, we can say real-time web is social by default and it is not true the contrary (even if WEB-r comes before Web 2.0). The WEB-r model is called TRUE-realtime web to highlight the differences with the defective (de facto) model of real-time web generally perceived (interaction between human<->userinterface instead of correct userinterface<->server / this was a marketing issue in the past). From the industry point of view, this model of (general) real-time Internet can also be defined as electronic web, that comes with the intrinsic meaning of not being limited to the web side of the Net (e.g. automation), and with the direct reference to its server/rest-of-the-world perspective as a mechanism of a single clock.
Dedicated server-side programming language: WIMS++.
Examples of real-time web are Facebook’s newsfeed, and Twitter, implemented in social networking, search, and news sites. Benefits are said to include increased user engagement (“flow”) and decreased server loads. In December 2009 real-time search facilities were added to Google Search.
The absolutely first realtime web implementation worldwide have been the WIMS true-realtime server and its web apps in 2001-2011 (WIMS = Web Interactive Management System); based on the True-RealTime Web (WEB-r) model of above; built in WIMS++ (server built in Java) (serverside) and Adobe Flash (ex Macromedia Flash) (clientside). The true-realtime web model was born in 2000 at mc2labs.net by an Italian independent researcher.
A problem created by the rapid pace and huge volume of information created by real-time web technologies and practices is finding relevant information. One approach, known as real-time search, is the concept of searching for and finding information online as it is produced. Advancements in web search technology coupled with growing use of social media enable online activities to be queried as they occur. A traditional web search crawls and indexes web pages periodically, returning results based on relevance to the search query. Google Real-Time Search was available in Google Search until July 2011.
Real-time computing (RTC), or reactive computing is the computer science term for hardware and software systems subject to a “real-time constraint”, for example from event to system response. Real-time programs must guarantee response within specified time constraints, often referred to as “deadlines”.
Real-time responses are often understood to be in the order of milliseconds, and sometimes microseconds. A system not specified as operating in real time cannot usually guarantee a response within any timeframe, although typical or expected response times may be given. Real-time processing fails if not completed within a specified deadline relative to an event; deadlines must always be met, regardless of system load.
A real-time system has been described as one which “controls an environment by receiving data, processing them, and returning the results sufficiently quickly to affect the environment at that time”. The term “real-time” is also used in simulation to mean that the simulation’s clock runs at the same speed as a real clock, and in process control and enterprise systems to mean “without significant delay”.
Real-time software may use one or more of the following: synchronous programming languages, real-time operating systems, and real-time networks, each of which provide essential frameworks on which to build a real-time software application.
Systems used for many mission critical applications must be real-time, such as for control of fly-by-wire aircraft, or anti-lock brakes, both of which demand immediate and accurate mechanical response.
A system is said to be real-time if the total correctness of an operation depends not only upon its logical correctness, but also upon the time in which it is performed. Real-time systems, as well as their deadlines, are classified by the consequence of missing a deadline:
- Hard – missing a deadline is a total system failure.
- Firm – infrequent deadline misses are tolerable, but may degrade the system’s quality of service. The usefulness of a result is zero after its deadline.
- Soft – the usefulness of a result degrades after its deadline, thereby degrading the system’s quality of service.
Thus, the goal of a hard real-time system is to ensure that all deadlines are met, but for soft real-time systems the goal becomes meeting a certain subset of deadlines in order to optimize some application-specific criteria. The particular criteria optimized depend on the application, but some typical examples include maximizing the number of deadlines met, minimizing the lateness of tasks and maximizing the number of high priority tasks meeting their deadlines.
The above is a brief about Real-Time Web. Watch this space for more updates on the latest Trends in Technology.