International Journal of Intelligent Engineering and Systems

7

Authors: Masaya Kumagai, Yasuo Musashi, Dennis Arturo Ludena Romana

We performed statistical analysis on the total PTR resource record (RR) based DNS query packet traffic from a university campus network to the top domain DNS server through March 14th, 2009, when the network servers in the campus network were under inbound SSH dictionary attack. The interesting results are obtained, as follows: (1) the network servers, especially those providing SSH services, generated the significant PTR RR based DNS query request packet traffic through 07:30-08:30 in March 14th, 2009, (2) we calculated sample variance for the DNS query request packet traffic, (3) the variance can change in a sharp manner through 07:30-08:30, (4) we developed a couple of DNS based SSH detection technologies by employing the PTR RR DNS query request packet traffic variance- and the DNS query keywords Euclid distance based methods, and (5) we evaluated and compared the both detection rates. As a result, although the both detection technologies take high detection rates, the Euclid distance based detection technology can take a low false positive rate than that of the variance based one, indicating that we can detect the inbound SSH dictionary attack to the network server in the campus network by observing the total PTR RR DNS query request packet traffic from the campus network.

8

Authors: Yongxin Feng, Wenbo Zhang

In wireless sensor network the bad distribution for cluster head was not taken into account in traditional clustering algorithm such as LEACH algorithm. However the distribution uniformity for the cluster head in wireless sensor networks is very critical, for the better cluster head distribution could effectively save the communication cost and prolong the the lifespan of the network. The math programming approach that we use in this paper is based on a variation of a maximal expected covering location model due to Daskin. Daskin introduced a variant of the MCLP that considers the possibility that facilities may be unable to respond to demand at all times. The resultant model was labeled as MEXCLP (Maximum Expected Covering Location Problem). So we put forward the MEXCLP algorithm for clustering according to the greatest expectations of coverage principle, in this algorithm the cluster head was taken regarded as the provider of services, the cluster head could provide service to the member nodes in the cluster. The algorithm considers the process of service failure (link failure, and so on), and it is based on the assumption of probability of the services failure, a reasonable choice through the head cluster node enables network nodes be served with the largest request number. From the simulation results can be see that the MEXCLP algorithm is more uniformed in finding head cluster, and under the same failure rate circumstances, MEXCLP algorithm may provide more efficient service and consume less energy than the LEACH algorithm. So this clustering algorithm could effectively and efficiently be suitable to the wireless sensor network and provide more reliable service for the sensor nodes in the cluster.

8

Authors: Yimin Qiu, Jinguang Gu, Hongbing Zhu, Yi Zhou

In the past years there has been an enormous growth in the use of Internet, and new real-time connectionoriented services like streaming technologies and mission-critical transaction-oriented services are in use and new ones are currently emerging. The research on more reliable network becomes an inevitable trend presently. MPLS is a next generation backbone architecture, which can speed up packet forwarding to destination by label switching. However, if there is not a backup LSP when the primary LSP fails, MPLS frames cannot be forwarded to destination. Therefore, fault recovery has become an important research area in MPLS Traffic Engineering. At present, Protection Switching can be approached by two famous methods, Makam and Haskin based on which other methods basically come into being. When the place of failure is away from ingress node, a problem will come out. These two famous methods both have their disadvantage. In order to minimize or eliminate their drawback, this thesis tries to do some exploration on the MPLS-based recovery model. The model in the thesis using the Reverse Backup Path to solve the loop of data back to the path is too long, and the simulation experiment shows that new method of MPLS-based recovery has less packet disorder and much lower delay and packet losses.