Distributed Real-time Monitoring with Accuracy Objectives”, KTH

Abstract. We introduce A-GAP, a protocol for continuous monitoring of network state variables with configurable accuracy. Network state variables are computed from device counters using aggregation functions, such as SUM, AVERAGE and MAX. In A-GAP, the accuracy is expressed in terms of the average error and is controlled by dynamically configuring filters in the management nodes. The protocol follows the push approach to monitoring and uses the concept of incremental aggregation on a self-stabilizing spanning tree. A-GAP is decentralized and asynchronous to achieve robustness and scalability. We provide some results from evaluating the protocol for an ISP topology (Abovenet) in several scenarios through simulation. The results show that we can effectively control the fundamental trade-off between accuracy and overhead. The protocol overhead can be reduced significantly by allowing only small error objectives. 1