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Wireless Internet of Things (IoT) devices share several features such as limited energy supply, low computing power, limited memory size, and vulnerable radio communication network. IETF proposed the Constrained Application Protocol (CoAP) for this type of network. This paper presents implementation of CoAP into an embedded IoT device used for smart Energy Storage System (ESS) under microgrid environment. Confirmable message type was adopted to provide reliable communication. Since the frame size of IEEE 802.15.4 physical layer was limited to 127 bytes, the header of 6LoWPAN and UDP was compressed to reduce fragmentation and reassembly overhead. Performance of the communication service was tested by measuring round trip time between two end nodes of developed system.

Device-to-device (D2D) communication has been becoming increasingly popular with the spread of mobile terminals including tablets and smart phones. D2D communication has received considerable attention due to its benefits of offloading cellular traffic and creating new applications such as location-aware services and content distribution. Recently, a new type of D2D communication, referred as “point-and-link communications”, was proposed to make establishing links between devices more intuitive and user-friendly. With this technique, a target device can be identified by simply choosing the target device image on the user's terminal display. In this paper, we propose an efficient object recognition algorithm for point and-link communications for mobile terminals. Considering the limited capabilities of mobile terminals, the algorithm should operate in real time with low complexity and low memory requirements. Due to the bandwidth limit, the feature size of each device must be lower than 300 bytes. The proposed algorithm was optimized for each type of target including faces, devices and signboards.

Recently, 3GPP introduced QoS control architecture model to support QoS-enabled multimedia services such as VoIP. This model would be appropriate to apply the peer-to-peer services so that the procedure for the session establishment is quite a complicate to provide the connectivity between two parties. This paper proposes the QoS control architecture model using API for the support of streaming services, which is client-server service type. It is different from the peer-to-peer service type of VoIP. The paper will show the effectiveness and the simplicity of the proposed model to support streaming service. In addition either a Network operator or a (3rd party) service provider could own the streaming service server so that service openness may be easily achieved.

WDM networks using wavelength routing are considered to be potential candidates for the next generation backbone networks. One of the critical issues of the future network is a provision of proper QoS guarantees for a wide variety of multimedia multicast service. This paper concerns with the problem of optical multicast routing with QoS guarantees in WDM networks. Using Virtual Source (VS) nodes, we proposes a new MCRWA method for a multicast session, combining the VS-based tree method with Multi-Wavelength Minimum Interference Path Routing (MW-MIPR). This paper also proposes a QoS MCRWA method in combination with QoS constraints and a recovery strategy based on the differentiated QoS service model to provide QoS guarantee for a wide variety of multicast application in the next generation optical networks.

A “virtual private network (VPN) over Internet” has the benefit of being cost-effective and flexible. Given the increasing demand for high bandwidth Internet and the demand for QoS assurances in a “VPN over Internet”, IP/generalized multi-protocol label switching (GMPLS) based on a control plane combined with a high-bandwidth, dense-wavelength division multiplexing (DWDM) optical network is seen as a very favorable approach for realizing the future “optical VPN (OVPN) over IP/GMPLS over DWDM”. In this paper, we suggest a new routing algorithm for establishing optimal optical-label switched paths (O-LSPs) in OVPN, called the Multi-Wavelength-Minimum Interference Path Routing (MW-MIPR), to provide more improved performance for connection blocking probability with consideration for potential future network’s congestion status. The proposed algorithm improves wavelength utiliza-tion by choosing route that does not interfere too much with many potential future connection requests. Simulation results show that proposed MW-MIPR algorithm achieves more enhanced blocking probability than dynamic routing (DR) that yields the best performance among previous routing and wavelength assignment (RWA) algorithms.