Abstract: A system that provides secure transmission of data between a subscriber's PC and an online service provider (OLS) over an Ethernet WAN. The system includes a remote transceiver unit located at a subscriber site and connected to the subscriber's PC; a central transceiver unit located at a telephone central office and connected to the remote transceiver unit over a twisted pair network and also connected to a WAN; an authorization server that is connected to the WAN; and one or more OLSs, which may include Internet service providers, connected to the WAN. Security of transmission is provided through a method in which only subscriber transmissions directed to a session-specific OLS are allowed to pass through the central transceiver unit onto the WAN, and only unicast transmissions from authorized OLSs are allowed to pass through the central transceiver unit to the subscriber port of the remote transceiver unit. Broadcast transmissions are minimized in favor of unicast messages.

Abstract: A method of bit rate adaption between a user data rate and an adapter data rate using the ECMA 102 protocol. The user data is received from a user terminal at a user data rate, the rate adapted data is transmitted at an adapted data rate, and the adapted data rate is greater than the user data rate. The user data is either in a asynchronous or a synchronous format and contains a start element and at least one stop element. The method involves the steps of: (1) converting the user data into an intermediate data; (2) storing the intermediate data in a receive buffer; (3) only if the user data is in an asynchronous data format, adding stop elements to the intermediate data; (4) transferring the intermediate data in the receive buffer to an intermediate buffer; (5) constructing a frame using data from the intermediate buffer; (6) storing the frame in a transmit buffer, and; (7) transmitting the frame where the step of transmitting changes the frame into the rate adapted data.

Abstract: A method of bit rate de-adaption between an adapted data rate and a user data rate using the ECMA 102 protocol. The user data is transmitted from a data adapter to a user terminal at a first data rate, the adapted data is received by the data adapter at a second data rate, and the second data rate is greater than the first data rate. The adapted data contains a start element and a plurality of data elements while the user data contains a start element and at least one stop element.