The transport service is a facility that is part of the lower architecture of Con-nect. It consists of data structures in the Con-nect spool file and programs which implement the transport service functions and provide the interface between the transport service and applications (e.g. Con-nect) which make use of it. The system architecture of the transport service is based on queues in which transport items are stored between stages of processing and queue server programs.

The transport service facilitates the asynchronous distribution of data from one originator to one or multiple recipients in a store-and-forward manner (returning notifications which report successful or unsuccessful delivery to the intended recipients, using the same store-and-forward distribution mechanism - if requested). While the transport service is primarily intended for mediating electronic mail, the generality of this service allows it to be used as a basis for other types of applications as well.