Softswitch Platform Down The Phone Number Classification

The use of IP Multimedia Subsystem and soft switch technology makes the next generation of telecommunication network become IP-based network, as well as intelligence of the terminal. The probability of DoS(Denial of Service) attack from Internet to telecommunication network is increasing unceasingly. Hence, the telecommunication network is faced with more and more safety issues. Operators want to provide more secure and reliable network services, such as firewalls, intrusion detection, and differential service and so on. All of these services require a search function based on the called phone number in order to differentiate the calling population whose called number is specially protected or important. Then work out a corresponding security management strategy or reasonable flow control measures according to actual demands and operation states of the network. Therefore, it is of great value to do the research on the phone number classification method.In this paper we review the various classification techniques which are widely used these days and propose a new algorithm based on Multi-branch Trie and Bitmap Index (MTBI). After improving the trees divided by value, we combine it with the MTBI and apply them to the design of the phone number classification system under the soft-switch platform. Contributions are:i. Analyzing the character of the rule set, a enhanced algorithm is presented based on the trees divided by value algorithm. The enhanced algorithm reduces the dimension of the selection of endpoint's value from 5 to 1, which leaves out judgments of the domain and therefore decreases the algorithm's space complexity. Simulation results show that the algorithm shows a good performance when there're a small number of rules in the rule set.ii. After analysis of the deficiency of the trees divided by value, we propose an phone number classification algorithm based on Multi-branch Trie and Bitmap Index. The MTBI overcomes the reconstruction of the searching structure and the fast expansion of searching tree's depth when a large number of rules'updating occurs as the algorithm of trees divided by value. Since the Trie tree structure is simple and the searching depth is related to the length of the keywords, MTBI uses the prefix part of the rule phone number to construct the multi-branch Trie structure. Also Bitmap index is applied to the trail part of the rule number to reduce the storage cost to a reasonable level and further enhance the search speed.?iii. Based on the combination of the MTBI and the trees divided by value algorithm, we design a phone number classification system under the soft-switch platform, and give detailed descriptions of each function blocks. By now, a complete solution for the phone number classification is provided.