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Introducing WebSocket: Bringing Sockets to the Web

Introducing WebSocket: Bringing Sockets to the Web
The Problem: Low Latency Client-Server and Server-Client Connections The web has been largely built around the so-called request/response paradigm of HTTP. A client loads up a web page and then nothing happens until the user clicks onto the next page. Around 2005, AJAX started to make the web feel more dynamic. Still, all HTTP communication was steered by the client, which required user interaction or periodic polling to load new data from the server. However, all of these work-arounds share one problem: They carry the overhead of HTTP, which doesn't make them well suited for low latency applications. Introducing WebSocket: Bringing Sockets to the Web The WebSocket specification defines an API establishing "socket" connections between a web browser and a server. Getting Started You open up a WebSocket connection simply by calling the WebSocket constructor: var connection = new WebSocket(' ['soap', 'xmpp']); Notice the ws:. Communicating with the Server Related:

Start Using HTML5 WebSockets Today One of the coolest new features of HTML5 is WebSockets, which let us talk to the server without using AJAX requests. In this tutorial, we'll review the process of running a WebSocket server in PHP, and then building a client to send and receive messages to it over the WebSocket protocol. What are WebSockets? WebSockets is a technique for two-way communication over one (TCP) socket, a type of PUSH technology. At the moment, it's still being standardized by the W3C; however, the latest versions of Chrome and Safari have support for WebSockets. What do WebSockets Replace? Websockets can replace long-polling. Many Ajax applications makes use of the above – this can often be attributed to poor resource utilization. Wouldn't it be great if the server could wake up one morning and send its data to clients who are willing to listen without some sort of pre established connection? Step 1: Get the WebSocket Server This tutorial will focus more on the client building rather than server implementation.

Node.js Websocket Examples with What are Websockets? Over the past few years, a new type of communication started to emerge on the web and in mobile apps, called websockets. This protocol has been long-awaited and was finally standardized by the IETF in 2011, paving the way for widespread use. This new protocol opens up a much faster and more efficient line of communication to the client. Even better, since the connection never dies we finally have full-duplex communication available to us, meaning we can push data to the client instead of having to wait for them to ask for data from the server. How do Websockets Work? At its core, a websocket is just a TCP connection that allows for full-duplex communication, meaning either side of the connection can send data to the other, even at the same time. To establish this connection, the protocol actually initiates the handshake as a normal HTTP request, but then gets 'upgraded' using the upgrade request HTTP header, like this: Some Websocket Examples Establishing the Connection

buildar/getting_started_with_webrtc The WebSocket API Abstract This specification defines an API that enables Web pages to use the WebSocket protocol (defined by the IETF) for two-way communication with a remote host. Status of This document This section describes the status of this document at the time of its publication. If you wish to make comments regarding this document, you can enter feedback using this form: You can also e-mail feedback to (subscribe, archives), or (subscribe, archives). Implementors should be aware that this specification is not stable. The latest stable version of the editor's draft of this specification is always available on the W3C CVS server and in the WHATWG Subversion repository. Notifications of changes to this specification are sent along with notifications of changes to related specifications using the following mechanisms: E-mail notifications of changes Commit-Watchers mailing list (complete source diffs):

About WebSocket About HTML5 WebSocket The HTML5 WebSockets specification defines an API that enables web pages to use the WebSockets protocol for two-way communication with a remote host. It introduces the WebSocket interface and defines a full-duplex communication channel that operates through a single socket over the Web. HTML5 WebSockets provide an enormous reduction in unnecessary network traffic and latency compared to the unscalable polling and long-polling solutions that were used to simulate a full-duplex connection by maintaining two connections. HTML5 WebSockets account for network hazards such as proxies and firewalls, making streaming possible over any connection, and with the ability to support upstream and downstream communications over a single connection, HTML5 WebSockets-based applications place less burden on servers, allowing existing machines to support more concurrent connections. The WebSocket Protocol GET Using the HTML5 WebSocket API

Chat App Best Practice Guide with JavaScript APIs | PubNub One of the most common use-cases of PubNub data stream network is for chatting. It can be a standalone chat app, or a chat feature in a larger application or website. A good example of latter is the one seen on Twitter Periscope, where viewers can interact with the videocaster during a live video stream. Simulated image from an screenshot from Periscope by Monterey Bay Aquarium We work hard to make it easy for you to build your own apps, however, nothing is too easy- we get questions from many of you every day. So I picked up the common features that used in chat apps, and wrote up a use-cases based best practice guide. The guide includes basic chat features like, “Joining a chat room”, “Displaying how many users are currently online”, to “Retrieving past messages”, also features that improve your app’s user experience, such as “Showing an indicator when someone is typing”, as well as information on how to make your users chat messages secure, for example with using AES cryptography.

A Web RTC Tutorial With WebRTC, adding a peer-to-peer video chat to a site is as easy as child's play and the best part of it is that there is no need for your users to download plugins to use the service. There are two pieces needed to set up peer-to-peer video chat using WebRTC: an HTML5 compliant browser, and the proper code on your server. This blog will walk you through the steps to get a simple service up and running. WebRTC is part of the HTML5 standard and is still under development. Installing the Browser To install the browser, follow the steps here. /usr/lib/webkitgtk-1.0-0/libexec/GtkLauncher If you see a page with a Captcha, you're all set to go, but if you see a warning that your browser lacks support for PeerConnection video conferencing you need to track down the problem. Note that the following steps are only required if you want to host the signaling server yourself. Setting up the Server With the browser part cleared, we'll now turn to the server setup. <!

How HTML5 Web Sockets Interact With Proxy Servers With the recent explosion of WebSocket server implementations, a lot of questions have come up about how HTML5 Web Sockets deal with proxy servers, firewalls, and load-balancing routers. Will proxy servers automatically kill WebSocket connections? Do HTML5 Web Sockets handle firewalls and proxy server issues better than Comet? Are Web Sockets the silver bullet in seamless proxy server traversal? In this article, I’ll explain how HTML5 Web Sockets interact with proxy servers, load balancing routers, and firewalls. About HTML5 Web Sockets and Proxy Servers Let's start with some basic concepts: what exactly are HTML5 Web Sockets and proxy servers? HTML5 Web Sockets The HTML5 Web Sockets specification defines the Web Sockets API that enables web pages to use the Web Socket protocol for full-duplex communication with a remote host. Proxy Servers A proxy server is a server that acts as an intermediary between a client and another server (for example, a web server on the Internet). Let's recap.

Guía de HTML5 en PDF aprende desde cero el nuevo lenguaje de la web En nuestro recorrido por Latinoamérica compartiendo historias y tendencias de HTML5 empezamos a redactar esta guía para nuestros alumnos. Con HTML5 se está construyendo la web moderna. Vídeo, audio, geolocalización, nuevos componentes y etiquetas que son la base del gran cambio de internet en esta época. Con la guía tomarás las bases para iniciar y crear sitios y aplicaciones en HTML5 para PCs y teléfonos móviles. La guía está en producción permanente. HTTP vs WebSockets HTTP is like walkie-talkie; data transmission can happen from only one direction at a time. WebSocket is like telephone; data transmission can happen from both direction at the same time. Image source In HTTP both ends can transfer data but only one at a time. HTTP was not designed to be highly interactive. WebSocket Above limitations clearly suggest that there was a need for more reliable bi-directional (full-duplex) communication between two end points (in web-world known as client and server).