Let P be a set of n points in the plane. A geometric graph G on P is said to be locally gabriel if for every edge (u, v) in G, the disc with u and v as diameter does not contain any points of P that are neighbors of u or v in G. Motivated by applications in topology control of wireless networks, [KL03] initiated the study of this graph. An interesting combinatorial question is to bound the edge...

A medium access control (MAC) protocol for spread-spectrum ad hoc networks with dynamic channel allocation (DCA) is presented. DCA can support large systems with a smaller number of channels by dynamically assigning channels only when a node has a packet to transmit. The protocol extends cross layer, with the scheduling at the MAC, and assignment of channels at the physical layer by means of a ...

The way in which electric power depends on the topology of circuits with mixed voltage and current sources is examined. The power flowing in any steady-state DC circuit is shown to depend on a minimal set of key variables called fundamental node voltages and fundamental edge currents. Every steady-state DC circuit can be decomposed into a voltage controlled subcircuit and a current controlled s...

In the study of ad hoc sensor networks, clustering plays an important role in energy conservation therefore analyzing the mechanics of such topology can be helpful to make logistic decisions .Using the theory of complex network the topological model is extended, where we account for the probability of preferential attachment and anti preferential attachment policy of sensor nodes to analyze the...

With the current default settings of the OSPF parameters, the network takes several tens of seconds before recovering from a failure. The main component in this delay is the time required to detect the failure using Hello protocol. Failure detection time can be speeded up by reducing the value of HelloInterval. However, too small a value of HelloInterval will result in an increased chance of ne...

Topology control for ad hoc networks aims to increase effective network capacity and conserve energy. Most proposed algorithms assume the usage of isotropic antennas and thus only adjust the transmission power of each node. We propose a distributed topology control mechanism for ad hoc networks with directional antennas that adjusts antenna pattern (direction(s)) in addition to transmission pow...

Budget based network admission control (NAC) mechanisms can be categorized into four basically distinct approaches. Since they have different complexity and efficiency, we compare their resource utilization in different networking scenarios. Our results show that the network size, the connectivity, and the internal structure of the network have a significant impact on the resource efficiency. S...

Wireless sensor networks are the ultimate technology for communication that allows network nodes to communicate without the need for a fixed infrastructure and wires. They use electromagnetic waves, as the information transmission.The development of network technologies has prompted sensor folks to consider alternatives that reduce costs and complexity and to improve reliability. This paper add...

The dominant dynamics of sensor networks consist of using the energy of the sensor nodes to create the topology of hierarchical clustering using topology control protocols. The topology thus created will always have optimum number of nodes after using a certain amount of energy, vice versa optimum amount of energy expense to use a certain number of nodes. This paper attempts to find a relation ...

The development of integrating several wireless network technology make wireless network devices built everywhere. In 1999, IEEE proposes WiMAX broadband wireless technology which has high transmission bandwidth and wide coverage. There are more and more researches as abovementioned wireless technology to increase Mesh network technology which can easily increase network coverage. Intel[1] poin...