Flash Player 8.5 introduced a new version of AMF known as
AMF3 (AMF0 is still supported).
AMF3 supports the new ActionScript 3 data types, uses a more compact encoding
format and reduces redundant information by serializing recurring class
descriptions and strings by reference.
Strongly Typed Objects
In ActionScript 3.0, use flash.net.registerClassAlias to register an alias for a client class (serialization will include the alias when instances of the class are serialized). Without a registered alias, an instance is sent as an anonymous Object (ASObject). A client class alias must be registered before any instances are sent to the server or received from the client in order for them to be deserialized correctly.
Starting ActionScript 3.0 only object get/set properties are serialized.
Custom serialization and flash.util.IExternalizable
ActionScript 3.0 IExternalizable interface allows to control serialization of strongly typed classes.
ArrayCollection
ArrayCollection is serialized to com.TheSilentGroup.Fluorine.AMF3.ArrayCollection server class. You can create a new ArrayCollection instance on the server by passing an ArrayList object in the ArrayCollection constructor.
ByteArray
The ByteArray class provides methods and properties to optimize reading, writing, and working with binary data. A ByteArray object is serialized to com.TheSilentGroup.Fluorine.AMF3.ByteArray server class.