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Ahstract-Wireless Sensor Networks (WSNs) have been a focus for research in recent years. They enable data gathering across a wide range of domains and areas of interest from health service to environment monitoring, security, etc. Sensors are becoming cheaper, and as a result are being deployed in high density, at the same time; users' requirements of the network are changing frequently, they can even exceed the capabilities of the sensors in the network sometimes. The network is expected to operate for a long period of time with many nodes operating on batteries. These challenges have raised the attention to the problem of mission assignment in WSNs. Mission assignment aims at allocating tasks to specific sensors in the network -according to their capabilities-to answer users requirements while at the same time preserving the energy of the network. This paper approaches the problem of mission assignment from a geospatial perspective: because sensors' readings and data are associated with spatial properties of the sensors like their location and sensing range; spatial reasoning is an important aspect of mission assignment.However, spatial reasoning is still very limited in WSNs and has not received much attention because of the lack of standardized modelling of space. In the center of our approach an integration of two ontologies; the W3C semantic sensor network ontology (SSN) which describes sensor nodes in the network and GeoSPARQL (the OGC standard for modelling and reasoning about spatial data). We present Geospatial Sensor Mission Assignment algorithm (GeoSMA); a branch and bound algorithm based on the spatial functions and relations between tasks' and sensors' spatial properties. The aim is to find the most appropriate set of nodes to answer various missions required by the users.

How to measure and maintain connectivity is an important issue in ad hoc networks. A special case of such network is Wireless Sensor Networks (WSN), which are often deployed in harsh environments and also susceptible to a number of problems that may negatively affect the connectivity among the nodes. An additional factor that increases the cost of connectivity maintenance in ad hoc networks is when the nodes can move. When it comes to the WSN domain, this aspect is still more problematic, as the often small sensor nodes have in general a limited energy budget, and then should not use too much energy in the management of their connectivity. The goal of this work is to choose a topology for mobile WSN and improve the network connectivity as a whole while considering and influencing the energy consumption among all the nodes in the network. Different network topologies are considered and discussed. After evaluation of the pros and cons of the estimation quality when applied to each studied topology, a clustered hierarchical algorithm was chosen for network deployment. By means of a link estimator and considering different variables, a metric have been defined to estimate the link reliability. As a result, improved network connectivity is reported.

In any developing nation such as Nigeria, the level of her telecommunication and ICT development is an issue that requires adequate planning especially when consideration is given to the amount of traffic and the available bandwidth in the system. Tourism is one of the areas that the Nigerian Government is considering as a source of internally generated revenue and therefore, infrastructure such as traffic free wireless communication system and fast internet accesss need to be provided to woo tourists and make them feel at home. This cannot be achieved unless the traffic is modeled and its analyzed .Yankari Game Reserve is one of the tourist attraction located in Bauchi state, north-eastern Nigeria. Wireless Communication and internet traffic is analysed in this paper using erlang models to improve the systems quality of service. It is shown that a multi-server system is the most appropriate model to reduce amount of delay in a peak period. It is also proven that delay time is reduced significantly when the number of users increases in a multi-server system.

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