Asynchronous transfer mode and media access protocol interoperability apparatus and method

A unique simple and generic ABR-MAC interoperability approach is employed which minimizes the impact of a Host Digital Terminal (HDT) ATM switch ABR connection on individual Information Appliances (IAs present at customer premises) and by employing a suitable MAC protocol to transfer data to an ATM network interface buffer (ATM-NI) located at the HDT. To this end, a unique arrangement is employed to regulate the buffer storage unit status in an ATM-NI. More specifically, the arrangement monitors upstream data traffic from active IA-HDT connections and, additionally, any incipient IA-HDT connections. This is realized by employing dual ATM-NI buffer storage unit threshold values that are selected depending on a particular ATM-NI buffer storage providing the particular information appliance on an active connection with information to allow the information appliance to adjust its transmission unit capacity, namely, a low, i.e., first, threshold value and a high, i.e., second, threshold value. In a particular embodiment, a predetermined parameter (k) is defined to specify a number of frames that have elapsed before a next upstream ATM cell is to be transmitted to the ATM-NI buffer storage unit at the HDT. If the amount of data stored in the ATM-NI buffer storage unit is less than the low threshold value, this implies a normal "uncongested" state of operation of the ATM-NI buffer storage unit. If the amount of data in the ATM-NI buffer storage unit is greater than the low threshold value but less than the high threshold value, regulation of the rate of data being supplied to the ATM-NI buffer storage unit must be performed. If the amount of data stored in the ATM-NI buffer storage unit is greater than the high threshold value, transmission of additional data to it is not allowed.