OBEX is an acronym that stands for OBject EXchange, a protocol mostly used in the communications technology field. Because the Infrared Data Association maintains this protocol, it is also known as IrOBEX or Infrared OBEX.
Primarily designed for swapping binary objects between particular devices, this protocol is designed to function like HTTP, as it allows the user to connect to a server in much the same way. Once connected, the user can either make a request or provide objects to be transferred. Some of the objects that the user can chose to provide include files, pictures, calendar entries and business cards.
OBEX is usually associated with and optimized for ad-hoc wireless links. There was a time, however, when it was reserved for only infrared connections. Today, the protocol can run on most transport devices, TCP/IP, and Bluetooth®. Bluetooth® is a form of industry specification used for wireless personal area networks (PANs).
Most modern communications devices have OBEX built in. Personal digital assistants (PDAs) were the first communication devices to be run using this protocol, but it can also be found in many brands of cell phones. A number of office machines and computer operating systems also support the standard.
OBEX is often referred to as a session protocol or a binary HTTP protocol. With its binary transmissions, it uses a binary-formatted length value, also called Headers. The binary transmission allows for the exchange of information in reference to a particular request or an object.
With session support, the protocol can make a single transport connection branch off into several other related operations. In other words, if a transaction has been closed, the use of OBEX can resume the transaction with all information remaining untouched.