Earticle

The technology of Worldwide Interoperability for Microwave Access (WiMAX) is based on the IEEE 802.16 standard which enables the delivery of last mile wireless broadband access within tens of kilometers. Under a single base station, the coverage is much wider than WLAN and can reach a transmission rate of 70Mbps. In this paper, we study the implementation of WiMAX for university campuses in the Taichung metropolitan area. Feng Chia University is such a university with multiple campuses providing e-services to the university communities. We have integrated WiMAX with existing Wi-Fi and MESH networks in a three-layer configuration. As a result, the system capacity and performance of this crosscampus wireless network have both increased. We have improved the access coverage and quality such that the overall usage of the wireless network at Feng Chia University is also increased.

Due to the impact of the rapid popularization of Internet and e-commerce, most organizations and enterprises take great effort to protect their information systems against malicious attacks and invasions. The firewall is the most familiar method among relevant technologies for Internet security. However, the firewall systems in use today are either application software or utilities running on the personal computers or network nodes. It is very inconvenient to implement and manage the conventional firewalls. In order to make the management and construction of them easier without disrupting the existing network topology, we implement an embedded and distributed firewall system to safeguard the Internet. In this way, we combine the functions of the firewall and a central security policy server into an embedded system, which can be realized as a network interface card.

A scale-free routing protocol and algorithm in wireless sensor networks are studied in this paper. The algorithm could be used to form a WSN with a scale-free-network-like topology which helps shorten the length of the routing path. Together with the information fusion function involved in the scale-free routing protocol, the algorithm could dramatically reduce the redundancies of the datagram transferred in the WSN and thus improve the life cycle of WSN.

Nowadays, the rapid development of computer networks calls for highly distributed management technologies that aim at integration and automation. This paper then gives an overview of current management architectures for computer networks, and tries to apply P2P technologies to make up existing limitations in term of performance, scalability, flexibility, maintainability and reliability. Due to their characteristics, P2P technologies provide a prospective approach to implement inter-domain network management, moving towards cooperative management. Performance issues show that, appropriate manipulations especially by means of compressing the P2P traffic and P2P messages, are of great significance in utilizing P2P technologies for computer network management.

In this paper a new way of secret sharing algorithms expansion based on additional, linguistic stage, introduced for the generation of the secret shadow elements are presented. Such a part shall be generated in the form of a linguistic description of the shared data, built by defined sequential grammar. The introduction of linguistic formalism in this scheme will provide additional information required for revealing the secret previously split with any (m, n)-threshold scheme.

This paper proposes a MAC protocol called the Latency MAC (LMAC) protocol for wireless sensor networks. The proposed LMAC protocol aims at minimizing the power consumption caused by the idle listening problem through enlarging the data collection time. This study examines the latency constraint in wireless sensor networks and studies the tradeoff between extra latency and energy-efficiency. In the process of trading latency for energy-efficiency, there are many restrictions. Thus, this study analyzed these limitations and then tries to achieve the best tradeoff between latency and energy-efficiency according to these limitations. By increasing the arrival prediction accuracy of data packets, the simulation results show that the LMAC protocol indeed help the sensor nodes to consume less energy, especially for the wireless sensor networks with loose latency constraints or light traffic load.

In this paper we present a technique to allocate bandwidth to the clients as per the privileges. It means basically that each user can buy bandwidth which will be available as a premium, high and normal class bandwidth. As per the class a user buys he will be given a username and password. Using this username and password he will authenticate himself to the server. The server then provides bandwidth to that user for running the applications which fall within the bandwidth range of that class. The server queues all the packets coming to it from the internet connection and then sends them out on a priority basis which is defined by the class each user falls into.