Box-carring is a concept in distributed computing where multiple operations are grouped together and sent in a bundle. The purpose of box-carring is to increase the performance of the bundle of operations by reducing the latency associated with the round-trips between client and server. Thus, if 2 operations are bundled together, the results of the first operation may become the input for the second operation (via shared state or as parameters).

Box-carring was initially declared out of scope for SOAP and to my knowledge has not yet been standardized. Box-carring is a service design issue.