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Multi-functional USN Gateway (MUG) is a multipurpose system combining a mesh router and a sensor gateway. The paper presents the design and implementation of the MUG system and the test-bed to verify the MUG system. MUG combines IEEE 802. l1n based Wi-Fi mesh router functions and USN gateway functions. MUG supports IP sensor networks based on 6LoWPAN and non IP sensor networks based on ZigBee. MUG also provides various backhaul network interfaces inc1uding WiBro, HSDP A, and Ethemet Interfaces. We veri한 the feasibiliη of the MUG system through implementation and evaluate the performance by installing and testing several MUG systems in the test-bed.

In this paper, we propose a new prioritized Optical Burst Switching (OBS) protocol based on a hop count, which can provide an efficient utilization in optical Wireless networks. Under several legacy schemes, a switch drops the burst with a shorter time among ones regardless of its traversed hop counts. As a result, the dropped burst that have been traversed more hops might cause to waste bandwidth than the one traversed a few hops. Noting that this problem, we propose the Just Enough Time (JET) with a hop count scheme which can reduce the wasted bandwidth by prioritizing the burst traversed more hops over others. From the simulation result, we show that the proposed scheme is advantageous over the legacy schemes in terms of the burst blocking probability and the link utilization.

As the importance of non-functional requirements has increased, many researchers have become interested in the software development process for non-functional requirements inc1uding the notation, modeling, and assessment of non-functional requirements. However, the characteristics of non-functional requirements are so sophisticated and there are many topics which have not been solved until now. In order to address one of the unsolved problems, we propose a systematic software development process to support the management of non-functional requirements. The process consists of six steps, each of which is composed of detailed activities. Using the proposed process, the non-미nctional requirements can be managed and modeled more effectively and systematically than previous ones.

The Electromagnetic Interference could occur due to power line on the telecommunication service. The Countermeasure is practised by legal law. Various affecting factors are described in the law. In this paper, an effect by pipeline especially in the ground, power feeding plant, and curved railway sector is analyzed as environmental factors which are not included in the law. By the practical measurement, it appears that the measured voltages on the spots with underground pipeline are grouped into lower voltage level, induced voltage tends to be high near power feeding plant, and also in the curved railway line. These analytical results can be meaningly considered in the application of countermeasure.

The Quality of Experience (QoE) of next Generation wired/wireless network seπices based upon IP networking is becoming a popular issue in recent years. The user experience of Internet services such as IPTV, online game, web surfing and etc, are becoming the most desirable factors to service providers to improve service performance and customer’s satisfaction. However, collecting user experience from customers and obtaining the QoE parameters from the Quality of Service (QoS) parameters such as bandwidth, delay, jitter or admission control algorithm, are difficult subjects because of the various service 쇼pes and user characteristics. In this paper, we propose a framework which contains service classification, QoE analysis and service enhancement steps for a suitable QoE measurement and management protocol. We define the user satisfaction indicators of the Internet services, classi다r the categories of each type of services, and analyse the Key Performance Indicator (KPI) in each type of services to perform the QoS parameters and improving the service qualities.

In this study, we realized the broadband home gateway system of dual mode based upon EDR 2-3Mbps transmission speed and 300Mbps of 802.11n, In broadcasting and telecommunication convergence networks to deliver multimedia services, hi양l-quality home. The bluetooth module is designed to use general low rate data speed service and the 802.11n module also is designed to use high rate speed service at various home network situation. The dual mode home gateway system, bluetooth and 802.11n module, is well realized for many specification such as emission power, spurious power, impedance matching, frequency channel test.