ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Sockets
Binary client sockets
Flash Player 9 and later, Adobe AIR 1.0 and later
A binary socket connection is similar to an XML socket except that the client and server are not limited to exchanging
XML messages. Instead, the connection can transfer data as binary information. Thus, you can connect to a wider
range of services, including mail servers (POP3, SMTP, and IMAP), and news servers (NNTP).
Socket class
Flash Player 9 and later, Adobe AIR 1.0 and later
The Socket class enables you to make socket connections and to read and write raw binary data. The Socket class is
useful for interoperating with servers that use binary protocols. By using binary socket connections, you can write code
that interacts with several different Internet protocols, such as POP3, SMTP, IMAP, and NNTP. This interaction, in
turn, enables your applications to connect to mail and news servers.
Flash Player can interface with a server by using the binary protocol of that server directly. Some servers use the bigendian
byte order, and some use the little-endian byte order. Most servers on the Internet use the big-endian byte order
because “network byte order” is big-endian. The little-endian byte order is popular because the Intel® x86 architecture
uses it. You should use the endian byte order that matches the byte order of the server that is sending or receiving data.
All operations that are performed by the IDataInput and IDataOutput interfaces, and the classes that implement those
interfaces (ByteArray, Socket, and URLStream), are encoded by default in big-endian format; that is, with the most
significant byte first. This default byte order was chosen to match Java and the official network byte order. To change
whether big-endian or little-endian byte order is used, you can set the endian property to Endian.BIG_ENDIAN or
Endian.LITTLE_ENDIAN.
The Socket class inherits all the methods defined by the IDataInput and IDataOutput interfaces (located in the
flash.utils package). Those methods must be used to write to and read from the Socket.
For more information, see:
Socket
IDataInput
IDataOutput
socketData event
Secure client sockets (AIR)
Adobe AIR 2 and later
You can use the SecureSocket class to connect to socket servers that use Secure Sockets Layer version 4 (SSLv4) or
Transport Layer Security version 1 (TLSv1). A secure socket provides three benefits: server authentication, data
integrity, and message confidentiality. The runtime authenticates a server using the server certificate and its
relationship to the root or intermediate certificate authority certificates in the user’s trust store. The runtime relies on
the cryptography algorithms used by the SSL and TLS protocol implementations to provide data integrity and message
confidentiality.
When you connect to a server using the SecureSocket object, the runtime validates the server certificate using the
certificate trust store. On Windows and Mac, the operating system provides the trust store. On Linux, the runtime
provides its own trust store.
Last updated 6/6/2012
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