如何建立浏览器对浏览器(点对点)连接?

我如何写一个网站使用 HTML5CSSJavaScript在客户端,将允许 一旦页面加载,直接在客户端浏览器之间建立 tcp/ip 连接

我需要这样做,以减少延迟,因为网站将要求从一个用户的输入传输到另一个用户尽快,所以发送数据从客户端 A 到服务器,然后到客户端 B 是不是一个好的选择。

我读了以前关于这个主题的文章,但是没有可用的解决方案/例子。据我所知,客户端之间的直接连接可以使用像 Silverlight、 Java 或 Flash 这样的插件。

有没有不需要插件的解决方案? 我想只使用 JavaScript。

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I'll have to disappoint you - this is currently not possible with just JavaScript. Websockets (and Socket.IO) allow a socket-like connection between the client and the server, but not between clients. Your option is a plugin - be it Flash, Silverlight, Java or custom-made.

What you can do is use socket.io and emulate that by writing a simple proxy server.

I would like to turn your attention to the fact, that most users nowadays are behind NAT or firewalls, and this means that you can't easily establish incoming connection to user's computer. So your idea would (if ever possible) work only in some cases and will bring extra complexity to your solution. So client-server system with possibly persistent connection (using websockets or socket.io) is a better option.

Here on Stackoverflow are several topics about P2P connections in browsers:

  1. Will HTML5 allow web apps to make peer-to-peer HTTP connections?
  2. What techniques are available to do P2P in the browser?
  3. Does HTML5 Support Peer-to-Peer (and not just WebSockets)
  4. Can HTML5 Websockets connect 2 clients (browsers) directly without using a server (P2P)
  5. Is it possible to create peer-to-peer connections in a web browser?
  6. Do websockets allow for p2p (browser to browser) communication?
  7. HTML 5 Peer to Peer Video Possibilities?
  8. Is WebRTC implemented in any browsers yet?

As mentioned in most of the topicts, both 2008 HTML5 working drafts were having a section "Peer-to-peer connections":

Since the W3C Working Draft 12 February 2009 the section "Peer-to-peer connections" disappeared. But this P2P connection is not gone. It's back under the name PeerConnection within the WebRTC (Real-Time Communications) specifications:

Since 31 October 2011, the W3C Editor's Draft is an official Working draft:

The only implementation of the PeerConnection (UDP based) exists in the modified WebKit by the Ericsson labs (May 2011), which is working quite well. Some patches are in WebKit now (Oct. 2011 -- see updates below!):

Additionally, the WebRTC initiative is a project by Google, Mozilla and Opera. Thus, they are continuing the specification on PeerConnection:

Probably Chrome (uses WebKit) will be the first major browser supporting WebRTC with PeerConnection:

Since 18th January 2012, Chrome is supporting WebRTC as well. It can be uses in the Dev channel (Windows, OSX, Linux) and the Canary build (Windows and OSX) by enabling it under chrome://flags. It only only supports MediaStream like Video and audio and can be tested with several Demos. Transferring application data like String/ArrayBuffer/... is not supported until now.

Since 16th March 2012, the WebRTC Editor's Draft separates a "Peer-to-peer Data API" to send and receive generic application data (String, ArrayBuffer and Blob). Chromium wants to implement the Data API soon (10th April 2012).

On April, 3rd, Mozilla published a first working example on WebRTC for Firefox as well.

DataChannel is planned for version 25 of Chrome, behind a flag, meanwhile it can be tested in Firefox Nightly/Aurora (12th December 2012):

2018: DataChannels are still experimental, but available in current versions of Chrome and Firefox: