Wireless sensor networks provide the means for gathering vast amounts of data from physical phenomena, and as such they are being used for applications such as precision agriculture, habitat monitoring, and others. However, there is a need to provide higher level abstractions for the development of applications, since accessing the data from wireless sensor networks currently implies dealing with very low-level constructs. We propose TinySOA, a serviceoriented architecture that allows programmers to access wireless sensor networks from their applications by using a simple service-oriented API via the language of their choice. We show an implementation of TinySOA and the results of an experiment where programmers developed an application that exemplifies how easy Internet applications can integrate sensor networks.

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Our paper explores the issue of how to provide appropriate quality of service mechanisms closely integrated with flexible mobility management in wireless local area networks. We consider them as access networks of choice for the high performance Wireless Mobile Internet. We present a hierarchical QoS architecture that extends Differentiated Services (DiffServ) to mobile hosts in a wireless environment.Our approach is based on controlling several parameters of a wireless LAN cell: the limited geographical span to ensure the same high bit rate for all hosts, the constrained rate of traffic sources to limit the use of the channel in function of the required QoS and the limited number of active hosts to keep the load sufficiently low. The QoS management is coupled with mobility management at the IP level. We use a micro-mobility scheme implemented in the IPv6 layer with fast hand-offs between adjacent cells. Micro-mobility avoids address translation, traffic tunneling, and enables fast handoffs. We give some details of experiments to show the quality of service differentiation over the 802.11b network. KeywordsQoS support in wireless access networks, micro-mobility management mechanisms, handover and admission control, 802.11 WLAN, IPv6

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We present a pragmatic view of different approaches used to guarantee data delivery in a deployable marine habitat monitoring system, composed of a two-tier dual frequency (2.4 GHz/900 MHz) hierarchical wireless sensor network (WSN). We cover endto-end application layer aspects. At the lower tier, we preconfigured endpoint (EP) transceivers for automatic data acquisition and wireless transfer using their native Application Program Interface (API) framework. These endpoints communicate with a more powerful intermediate cluster-head (CLH) system. At the upper tier, we deployed a modified low level 8-bit "Lighter" version of the well-known web application protocol called JavaScript Object Notation (JSON, or in our case LJSON) for back and forth CLH to BS validated message exchange. These LJSON messages are converted by the BS to 16-bit JSON and vice versa, for remote Internet interaction. And finally, the BS software establishes Internet Protocol (IP) client socket connections with a remote custom JSON service, in charge of marine habitat sensor data reception, verification, and nonvolatile database storage.