Impact of mobility models on clustering based routing protocols in mobile WSNs

This paper presents comparison of different hierarchical (position and non-position based) protocols with respect to different mobility models. Previous work mainly focuses on static networks or at most a single mobility model. Using only one mobility model may not predict the behavior of routing protocol accurately. Simulation results show that mobility has large impact on the behavior of WSN routing protocols. Also, position based routing protocols performs better in terms of packet delivery compared to non position based routing protocols

TransSMS: A Multi-Lingual SMS Tool

TransSMS is a multilingual SMS solution developed under the Intercultural Collaboration Experiment 2002 (ICE 2002). It provides features that enable users to send and receive text messages in different languages. At the moment, the languages supported are Malay, Japanese, Korean, Chinese and English. TransSMS provides two main features: (1) translating a text message from one language to another and sending the translated text as SMS; (2) `read' the translated text to the user. The second feature is useful for tourists who do not speak the language of the country that he is visiting. TransSMS can be accessed via the Web or a Java-enabled phone

Load Sharing as a Power Management Strategy for Mobile Computers

Load sharing has traditionally been used to improve system performance in distributed networks by transferring jobs from heavily loaded hosts to idle or lightly loaded hosts. Performance is improved by distributing workload more evenly among hosts, thus better utilising system resources. This thesis investigates the use of load sharing for a different purpose, that is as a power management strategy for mobile computers. Since mobile computers operate on limited battery power, which is a scarce resource, and there is unlikely to be a vast improvement in battery capacity in the near future, it is vital that power utilisation is managed efficiently and economically. The power management strategy proposed in this thesis is based on the concept of load sharing. The strategy attempts to reduce power consumption by the CPU, which is one of the components consuming a substantial amount of power, by off-loading computations from a mobile computer to a fixed host. A load sharing algorithm which selects suitable jobs for remote execution is proposed. When designing the algorithm, the inherent limitation of wireless networks must be taken into account. For example, low bandwidth means that communications delays are no longer negligible; sending and receiving messages must also be considered carefully as transmitting and receiving also consume a substantial amount of power. Consequently, when performing load sharing on wireless networks, more constraints have to be dealt with compared to when performing load sharing on fixed networks. In addition to reducing power consumption, transferring jobs for remote execution also gives users access to faster machines, thus improving response time. This study identifies the conditions and factors which make job transfer a viable option. The results obtained show that under suitable conditions, load sharing can extend battery lifetime significantly. Since stability is an important concern when designing load sharing algorithms, this issue is also addressed by this study

Power Conservation Strategy for Mobile Computers Using Load Sharing

Power management is an important aspect of mobile computing. Previous works on power conservation have concentrated on the hardware approach. In this paper, we propose a different approach of power conservation strategy for mobile computers which is based on the concept of load sharing. User jobs are transferred from a mobile host to a fixed host to reduce power consumption by the CPU. Simulation results show that under suitable conditions, transferring job can extend battery lifetime by up to 20%. Transferring jobs to a fixed host does not only extend battery lifetime but also gives users access to faster machines, hence improving job response time

CBE-ABR: a cluster based enhanced routing protocol for ad hoc mobile networks

A wireless ad hoc network is a collection of two or more devices with wireless communications and networking capabilities that communicate with each other without the aid of any centralized administrators. The network topology is dynamic, because the connectivity among the nodes may vary with time due to node mobility, departures and new arrivals. Hence, the need for efficient routing protocols to allow the nodes to communicate. In a flat topology, all nodes are of the same level and functionality, thus making it simple and efficient for smaller networks. However, when the network is large with sparse nodes, the routing information becomes more complex. This is when cluster-based techniques become useful to tackle such situations. In a cluster-based routing, all nodes in the network are dynamically organised into partitions called groups or clusters. These clusters are then combined into larger partitions to help maintain a relatively stable network topology