PROTOCOL FOR TRANSMITTING MESSAGES IN A NETWORK

A method for transmitting voice signals, including user names--alphabetic and/or spoken, and data messages, including network addresses, among sites of a network of store-and-forward messaging system sites using telephone lines. A preferred embodiment of the method for transmitting data messages and voice signals between sending and receiving store-and-forward messaging sites of the network of messaging systems connected by one or more telephone lines includes the steps of: (a) placing a telephone call form the sending site to the receiving site to a predetermined telephone number over one of the telephone lines; (b) connecting data transmission and reception apparatus to the telephone line at the sending and receiving sites; (c) exchanging predetermined control commands and data messages using the data apparatus at the two sites, the commands specifying a communications procedure; (d) disabling the data apparatus from exchanging control commands and data messages and connecting voice transmission and reception apparatus to the telephone line at the two sites; (e) transmitting voice signals between the two sites using the voice apparatus; (f) enabling the data apparatus for exchanging control commands and data messages at the two sites; (g) exchanging delivery information using the data apparatus at the two sites, which information indicates the success or failure of the voice signals transmission, and further communication procedure; and (h) one of the sites going on-hook.