OBject EXchange - Comparison To HTTP

Comparison To HTTP

OBEX is similar in design and function to HTTP in providing the client with a reliable transport for connecting to a server and may then request or provide objects. But OBEX differs in many important respects:

• HTTP is normally layered above a TCP/IP link. OBEX is commonly implemented on an IrLAP/IrLMP/Tiny TP stack on an IrDA device. In Bluetooth, OBEX is implemented on a Baseband/ACL/L2CAP/RFCOMM stack. Other such "bindings" of OBEX are possible.
• HTTP uses human-readable text, but OBEX uses binary-formatted type-length-value triplets named "Headers" to exchange information about a request or an object. These are much easier to parse by resource-limited devices.
• HTTP transactions are inherently stateless; generally a HTTP client opens a connection, makes a single request, receives its response, and either closes the connection or makes other unrelated requests. In OBEX, a single transport connection may bear many related operations. In fact, recent additions to the OBEX specification allow an abruptly closed transaction to be resumed with all state information intact.