Que Xirong

A quick CGA generation method

IPv6 uses Neighbor Discovery Protocol (NDP) to perform neighbor discovery in link-local scope. Since NDP itself has no security mechanism, Secure Neighbor Discovery protocol (SEND) is designed to protect NDP. SEND is based on the usage of an asymmetric key pair, and provides security mechanism by using Crypto Generated Address (CGA), digital signature and X.509 certification. Since CGA generation might be a time-consuming process, in this paper we present a modified CGA generation method that allows a newly connected node to generate a CGA address quickly. The method requires adding a key-pair server node to perform a part of CGA generation computation in advance. Since the most time-consuming calculation is performed on the server beforehand, the CGA generation time is shortened significantly.

The reasearch of hierarchy model for ad hoc network monitoring based on clustering

Ad hoc network has dynamic topology and large-scale nodes, for the purpose of monitoring and measurement in Ad hoc network, this paper proposes a new frame method of hierarchy model for monitoring, i.e., clusterhead selection mechanism. The mechanism designed a weight formula to handle the comprehensive update considering several factors such as distance, mobile rate, energy during the model establishment period, and three kinds of partial update means in real-time attributes management. It enhances load balance and structure stability in monitor hierarchy model and reduces calculation cost for unnecessary update. The simulation results show that the model using clusterhead selection mechanism was stable and efficient, which could apply to muti-scale networks, achieve conveniently and flexible deployment in Ad hoc network measurement system.

An immunity-based model for network intrusion detection

Network intrusion detection is one of the most popular research topics. Existing network-based intrusion detection systems have drawbacks in many aspects, among of which the two outstanding problems are the high ratio of false alarms and the lack of self-adaptation. An overview of the human immune system is presented and its salient features that can contribute to the design of competent network-based IDS are analyzed. Then a network-based intrusion detection model is described, which is inspired by the human immune system, and its characteristics are analyzed in full.

An approach to evaluate network performance based on hop-by-hop latencies

Understanding network performance especially in link level is becoming increasingly important for network management. This paper puts forward an approach to evaluate network performance based on hop-by-hop latencies from three different levels of granularity including interface granularity, city granularity and AS granularity. We use a set of large scaled traceroute data, from a number of sources which are PlanetLab nodes to other random selected destinations to accomplish the experimental study. The analysis results show that this approach can carry out network performance evaluation in a flexible and effective way.

Research on improved INSIGNIA based on network measurement

Due to the difficulty of QOS assurance for MANET(Mobile Ad hoc Network) in which the network topology changes dynamically, we improve the INSIGNIA protocol and proposes a method based on network measurement to provide better QOS assurance. This paper introduces the design principle and implementation of this method in details, and then introduces the system model of this method which is designed and implemented in OPNET simulation environment, describes the experiment process of verifying the feasibility and effectivily of this system model through simulation result.

Implementation of an ATM network and PSTN/N-ISDN interworking gateway

Broadband networks based on asynchronous transfer mode (ATM) have already been in commercial operation in some countries. The ATM has the capability of integrating various types of services into a single network. However, the traditional narrowband services still accounts for the major portion of the total telecommunication services. So it is necessary to implement the interworking function between the ATM network and PSTN/N-ISDN. We present a narrowband-broadband network interworking gateway (NB-IWG), in which we exploited the dynamic composite cell mechanism to adapt the voice traffic into ATM cells and implemented the signalling interworking between the narrowband and broadband network.