Electronic computer hardware and computer software, namely, multiplexers and software, used for accessing a remote office computer network, remote facsimile machine, and remote private branch exchange (PBX); electronic computer hardware and computer software for telecommuting, namely, providing access and communications by a remote user to an office computer network, and providing access and communications by users of a computer network to a remote user; electronic computer hardware and computer software for enabling a remote user's telephone, connected to the public switched telephone network (PSTN), to behave as a PBX extension of the user's office telephone system; electronic computer hardware and computer software to enable a user to connect to a computer network and receive incoming telephone calls with the use of a single telephone line without disconnecting them from the computer network; electronic computer hardware and computer software enabling an incoming telephone call, traveling over a telephone line that is currently being used by the recipient, to ring all individual telephones at the recipients home or office; electronic computer hardware and computer software to forward and route telephone calls directed to a user's office extension to a telephone at the user's home or some other remote location; and electronic computer hardware and computer software for forwarding and routing a user's electronic mail from one computer to another computer