PURPOSE: To improve the convenience of the store and forward exchange system by requesting a function unit program registered in the unit of function from the service user so as to conduct communication thereby allowing the service user to select only a required function and to use it.

CONSTITUTION: When a store and forward exchange 100 conducts storage exchange of a facsimile equipment from a terminal equipment T1 to a terminal equipment T2, a dial signal from the terminal equipment T1 such as a PB signal is received by a PB receiver 20A. The signal received and identified by the receiver 20A is fed to a request function analysis section 30, in which an information reception program p1, an information delete program p2 and an information transmission program p5 are on request. The result of analysis is fed to a request function selection section 40, by which any of the programs p1, p2, p5 in the function unit program storage section 10 is selected and the selected program is given to a program execution control section 50. The control section 50 converts the program into a sequence of facsimile store and forward and the service is conducted through the designation of a general sequence, a guidance sequence and a multiple address communication sequence.