Action Message Format(AMF) is a binary file format representing a serialized ActionScript object. The AMF file type is used throughout the Flash Player for data storage and data exchange. For example in the Flash Player AMF is used in SharedObjects, RemoteObjects, LocalConnection, ByteArray, RTMP, and all RPC operations. Some of the benefits of AMF include:

• File Size – AMF objects are very small and are compressed using zlib.
• Fast Serialization/ Deserialization – AMF is transformed using native C code in the Flash Player making it very fast. The AMF format was designed to serialize and deserialize quickly under low memory and slower CPU conditions making it perfect for the web. AMF data is parsed directly into objects, meaning there is no lag for interpretation or parsing of AMF making the creation of objects complete in a single pass.
• Native Types and Custom classes supported – You can serialize any object in Flash Player with the only exception being a displayObject.you can also map serialized objects back to custom class instanced provided the custom class is in the Flash Player when the AMF object is deserialized.

AMF existed in ActionScript 2 and was just called AMF as of ActionScript 3 the AMF protocol has been updated and is referred to as AMF3. For historical reasons the original AMF format is now referred to as AMF0. One of the main upgrades to AMF3 is that the object is now zlib compressed for faster transfer do to the smaller file size and the additional of data types that were released with ActionScript 3.

The two alternative frameworks that I am looking at are AMFPHP and Zend_AMF.

I’ve created the file in the root directory and specified in the Flex Compiler [Additional compiler arguments] the following string -locale en_US -services “services-config.xml”.

As soon as I clicked OK an error popped up with a message unable to open ‘services-config.xml’.   After trying varying things I was able to figure out that the problem was with the location of the file.  Simply placing the file at the root of the directory wasn’t the right location.  I needed to put the file in the same directory as the main MXML executable – after that the program worked as expected.