Message delivery with configurable assurances and features between two endpoints

In a messaging system that supports one or more message transports, a method of simplifying application development is provided by providing a single programming model that permits specifying one or more end-to-end message delivery assurances that are to be met at runtime, independent of a particular message transport or transports that are used at runtime, as opposed to specifying the particular message transport or transports at development time. The method comprises the acts of: defining a message channel interface that abstracts send and receive operations for exchanging messages over one or more message transports available for sending and receiving one or more messages; and defining, for use within a single programming model, a plurality of end-to-end message delivery assurances, each of which may be specified at runtime independent of the one or more available message transports, without specifying the one or more available message transports at development time, wherein the plurality of message delivery assurances comprise at least one of at least once message delivery, at most once message delivery, in order sent message delivery, and session time to live. The method can further comprise an act of: defining a plurality of local reliable message features, wherein each of the plurality of local reliable messaging features may be selected for use within the single programming model, and wherein the plurality of local reliable message features comprise at least one of a session state storage, message time to live, and transacted message buffering.