Improving quality of service for MIL-STD-188-220C

Quality of service (QoS) is an important component for the military communication networks. QoS for combat network radios can be critical for the efficiency and, indeed, the survival of a mission and its personnel. The implementation of QoS for the combat network radio networks and the tactical Internet is largely restricted to the utilization of priority (generally referred to as precedence in the fire support (FS) community). QoS for MIL-STD-188-220C is generally implemented in the data link layer using media access control (MAC) algorithms. A legitimate criticism of MIL-STD-188-220B/C in terms of implementing QoS is its restriction to three levels of precedence. An important consequence of the current implementation of QoS for the most urgent and time critical messages such as check-fires is that they are just another urgent message in terms of network access for all MIL-STD-188-220C MAC algorithms. The time criticality of these types of messages is obvious but even if there is a near universal requirement not to use urgent precedence messages, with current MAC implementations, urgent does not adequately provide the QoS needed for the almost immediate delivery of such messages. This paper presents two techniques for significantly improving the QoS performance for these most time critical messages. One additional level of precedence can be added to MIL-STD188-220C that improves the performance at all precedence levels. The study assumes a benign fully connected network. The paper discusses how the methodology used in this study could be applied to other communication systems.