Research On Probabilistic Distributed Lawful Interception

ABSTRACT:Lawful Interception refers to the behavior of law enforcement agencies that intercepted the communication process on the network since it is in need of Internet monitoring. It is the responsibility of network operators to provide this function. With the continuous development of Internet network technology, the way of communication has been greatly expanded, but the network structure and the characteristics of its transmission leaves great difficulties to lawful interception. How to effectively monitor the contents of the required extracted from the network and ensure that monitoring does not affect the behavior of both the process of communication, while preventing the monitoring operation is not being malicious use of monitoring programs is of the primary consideration.This paper is support by the Lawful Interception Developmental Project. Network router is chosen as the intercepted access point. The work described in this paper is mainly used in the interception of communications of network layer. The three network layer data identifications are used as the rules of monitoring. The main research and innovation are as follows:(1) Within the implementation of Lawful Interception solution at Network Layer the process of backup is discussed and the mechanism by using RPC is proposed. At the same time the method of rules copy is given, and it is achieved by programming. The mechanism has been proved that it can ensure integrity and consistency of the rules.(2) Base on the analysis of router performance degradation, a probabilistic distributed intercept algorithm is proposed. The algorithm and process of probabilistic distributed interception are minutely described. How to find out the intercepted probability is the main question of probabilistic distributed interception. Here three methods of probability calculation are proposed:calculation of average probability, calculation of probability based on flow number and calculation base on flow adjustment. Simulation results show that the performance of router is improved by adopting probabilistic distributed interception.