Methods and systems for reliably exchanging a message among collaborating
applications are disclosed. The methods and systems utilize a central
exchange infrastructure (XI) for executing collaborative business
processes among heterogeneous applications. Reliable message transmission
is guaranteed by an Exactly Once Protocol (EOP), in which a database
associated with the messaging and transport layer (MTL) of an
HTTP-compliant server is used for storing a message identifier and
comparing the message identifier to previously received message
identifiers. If there is no match, the XI facilitates an exchange of
message content of application data from a sending application to a
receiving application.