[FMS]运用as3开发RTMFP协议的P2P程序（基础篇）

[FMS]运用as3开发RTMFP协议的P2P程序（基础篇）作者：Jozsef Vass  译者：巴巴鲁

Adobe Flash Player 10 and Adobe AIR 1.5 introduce a new communications protocol, Real-Time Media Flow Protocol (RTMFP), whose low latency, end-to-end peering capability, security, and scalability make it especially well suited for developing real-time collaboration applications by not only providing superior user experience but also reducing operators' costs.

Adobe Flash Player 10 和 Adobe AIR 1.5 引入了一个新的通讯协议，Real-Time Media Flow Protocol (RTMFP)，其低延迟，端到端的对等功能，安全性和可扩展性使它特别适合开发实时协作应用，不仅提供卓越的用户体验，而且运营商降低成本。

Earlier versions of Flash Player use Real-Time Messaging Protocol (RTMP) and require Adobe Flash Media Server (FMS) for interactive collaboration applications (such as Adobe Acrobat Connect Pro) or audio/video streaming. While RTMP is an excellent choice for streaming media, shared objects, or remoting, it has limited ability of meeting real-time requirements of interactive audio and video communications.

早前的Flash Player 版本使用Real-Time Messaging Protocol (RTMP) 需要Adobe Flash Media Server (FMS)提供合作应用(例如 Adobe Acrobat Connect Pro)或者音频视频流。RTMP是streaming media, shared objects, 和 remoting连接的卓越选择，它满足实时性要求的交互式音频和视频通信的能力有限。

In order to use RTMFP, Flash Player endpoints must connect to an RTMFP-capable server, such as the Adobe Stratus beta service or a future version of FMS. Stratus is a hosted rendezvous service that aids establishing communications between Flash Player endpoints. Unlike FMS, Stratus does not support media relay, shared objects, scripting, etc. So by using Stratus, you can develop applications only where Flash Player endpoints are directly communicating with one another.

为了能够使用RTMFP，Flash Player 客户端必须连接到一个支持RTMFP协议的服务器，例如Adobe Stratus beta 服务器或者是新版本的FMS。Stratus 是一台用于Flash Player 客户端间通信的主机。不同于FMS, Stratus 不支持视频转播，shared objects,脚本，等。因此，使用Stratus，只可以开发Flash Player的客户端直接相互交流的应用程序。

Flash Player is already the market leader in online video distribution over the web. With the introduction of RTMFP and advanced media compression technologies, Flash Player 10 is well positioned as the leader in real-time communications as well.

Flash Player 已经在web视频领域占有重要的市场份额。由于采用RTMFP和先进的媒体压缩技术，将有利于Flash Player 10处于实时通信的领先地位。

In this article, I first highlight the benefits of using RTMFP in real-time communications applications. Second, I describe the new ActionScript 3.0 API for managing direct end-to-end RTMFP connections. Finally, I present our VideoPhone sample application.