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Use RTMFP for developing real-time collaboration applications

Codename Cirrus (previously codename Stratus) enables peer assisted networking using the Real Time Media Flow Protocol (RTMFP) within the Adobe Flash® Platform. RTMFP is the evolution of media delivery and real time communication over the Internet enabling peers on the network to assist in delivery. Cirrus was first introduced in 2008 as a rendezvous-only service that allowed clients to send data from client to client without passing through a server. Peer assisted networking debuted in Adobe Flash Player 10. Today, over one billion connected desktops across browsers and operating systems have Flash Player installed and support RTMFP.

The most important features of RTMFP include low latency, end-to-end peering capability, security and scalability. These properties make RTMFP especially well suited for developing real-time collaboration applications by not only providing superior user experience but also reducing cost for operators.

The Evolution of Media and Communication Delivery on the Flash Platform
Traditional Streaming / Communication with Unicast model RTMFP in Flash player 10.0 / Cirrus 1 RTMFP in Flash player 10.1 / Cirrus 2
e1 e2 e3
Traditional streaming requires a client to receive all data from a centralized server cluster. Scale is achieved by adding more servers First generation of RTMFP in Flash player 10.0 supported rendezvous. Media was always sourced from the publishing peer. Second generation of RTMFP supporting groups in Flash player 10.1 supports application-level multicast and reduces the load on the source publisher.

In order to use RTMFP, Flash Player endpoints must connect to an RTMFP-capable server, such as the Cirrus service. Cirrus is a beta, hosted rendezvous service that aids establishing communications between Flash Player endpoints.

Unlike Adobe Media Server, Cirrus does not support media relay, shared objects, scripting, etc. So by using Cirrus, you can only develop applications where Flash Player endpoints are directly communicating with each other.

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 10.1 and later releases are well positioned as the leader in real-time communications as well.

Cirrus on Adobe Labs is an Adobe-hosted service that facilitates Peer Assisted Networking. Cirrus does not support any server-side programming, media relay, or SharedObjects. Peer Assisted Networking technology is also available today in Adobe Media Server and Adobe LiveCycle® Collaboration Services.

Getting Started


Below you'll find references and links to help you participate in the Cirrus community.

Online Forum

Ask questions, discuss, and share feedback with other beta users and the engineering team in the online forums.

Please note that your submission of comments, ideas, feature requests and techniques on this and other Adobe maintained forums, as well as Adobe's right to use such materials, is governed by the Terms of Use.

Developer Center

Read more about RTMFP and Cirrus in the Flash Player Developer Center.

Visit the Flash Player Developer Center


If you want to learn more about releases on Labs as well as other Adobe technologies, visiting a user group or connecting with an Adobe Community Professional is a great place to start.

Product Details


The following resources are available to help you develop Cirrus-enabled applications:


What is Cirrus?
Cirrus is a hosted peer introduction service that facilitates establishing communication between Flash Player clients or Adobe AIR endpoints using RTMFP. Flash Player endpoints must stay connected to the server during the entire time of communications. Unlike Adobe Media Server, Cirrus does not stream video or support media relay, shared objects, or scripting. Cirrus is being made available as a beta service through Adobe Labs to allow our developer community to begin building applications using RTMFP.
What is the difference between Cirrus and a Adobe Media Server?
When using Cirrus, all data is encrypted and sent directly from client to client without touching a server. In comparison, applications using Adobe Media Server (and RTMP), data always flows through the server consuming both upload and download bandwidth from the server and clients. Cirrus is a preview service that has limitations including no custom server programming and no remote shared object support.
What is the difference between Cirrus and Adobe Live Cycle Collaboration Services?
LCCS is an Adobe hosted service that support RTMFP communication and is limited to basic introduction services. LCCS has support for a custom collaboration framework that includes pre-build user interfaces developers can use in Adobe Flash Builder™ and Adobe Flash Professional to create custom collaboration applications. LCCS is a commercial offering that developers can use for their business.
How do I get started with Cirrus?
You will need to register with your AdobeID to receive a unique developer key. The developer key can be used within your application to enable Cirrus. Sign up for a Cirrus developer key.
How much does Cirrus cost?
Cirrus is a free beta service. You will need to register with your Adobe ID to obtain a unique developer key.
Will Cirrus support Flash player 10.0?
Yes you can use Flash player 10.0 with Cirrus, however clients will not be able to join an RTMFP group, or leverage any of the new functionality. Clients earlier then Flash player 10.0 do not have support for RTMFP.
What are my options to use RTMFP in my commercial application?
Developers can use Adobe Media Server to develop and deploy RTMFP applications.
What makes Adobe’s Peer Assisted Networking technology different than other P2P applications?
RTMFP technology is a managed solution that can be controlled and managed, because a serve is always required to establish a peer connection (even though the data flows from Peer to Peer). RTMFP also respects the network because there is limited probing on the network, unlike unmanaged p2p applications. End users will need to accept peer communication each time to ensure privacy. RTMFP also has no additional client download to enable P2P because it’s built right into Flash player.

See answers to more frequently asked questions

System Requirements

Cirrus 2 requires that clients are using either Flash Player 10.1 (or greater) or AIR 2.0 (or greater). Flash player 10.0 or AIR 1.5 are supported but do not support RTMFP group participation.

Developers will need to provide a mechanism for exchanging peer identities between instances of application through their own intermediary (e.g., using HTTP web services, XML sockets to a presence server, etc.).

Release Notes

This release of the Cirrus is prerelease and is designed for evaluation purposes only. The service is not final; but, many portions of the technology are fully implemented and ready for you to try and discuss.


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