This paper presents a technique to integrate energy efficient ubiquitous sensors to work in a network for optimum control. This optimization technique can reduce power consumption by using wireless communicating sensors with a supervisor control. This supervisory control of the sensors gives it an advantage of being controllable from any embedded, desktop or Internet platform. Sensors for different purposes can work together to form a network which can be implemented in many environment like homes, city, hospitals and remote locations like mountains, forests etc. We employed an optimized sensing system and algorithm which reduced the number of sensors and power consumption.

The IEC 61850 presents the international standard for communication networks and systems in substations. The standard discusses the detail of the requirements and the architecture of substation automation system as well as data type and format. The IEC 61850 will substitute the traditional hardwired analog communication network using upto- date communication protocols for interoperability and reliable service. Basically all IEDs are connected through TCP/UDP and IP over Ethernet based LAN to exchange data. Thanks to the Ethernet frame, we can deploy any type of advanced communication technology for communication in substation. This paper discusses the technical issues associated with the communication networks integration in detail. We consider the possible topologies in Ethernet architecture with the topic in the discussion of the pros and cons of their architecture, and the required functionality of each network elements in detail. Several data types, e.g., GOOSE, time synchronization, and FTP, which uses different protocol stack, are used in substation system with their own delay requirements. Communication profiles for these services are discussed in this paper. We also present the system configuration, requirements, and architecture of the system. We establish a guideline to build a communication networks in substation automation system based on IEC 61850 and presents the ad-hoc based architecture for survivable substation automation system.

Routing algorithms with time and message complexities that are provably low and independent of the total number of nodes in the network are essential for the design and operation of very large scale wireless mobile ad hoc networks (MANETs). In this paper, we develop and analyze Cluster Overlay Broadcast (COB), a low-complexity routing algorithm for MANETs. COB runs on top of a one-hop cluster cover of the network, which can be created and maintained using, for instance, the Least Cluster Change (LCC) algorithm. We formally prove that the LCC algorithm maintains a cluster cover with a constant density of cluster leaders with minimal update cost. COB discovers routes by flooding (broadcasting) route requests through the network of cluster leaders with a doubling radius technique. Building on the constant density property of the network of cluster leaders, we formally prove that, if there exists a route from a source to a destination node with a minimum hop count of A, then COB discovers a route with at most O(/spl Delta/) hops from the source to the destination node in at most O(/spl Delta/) time and by sending at Most O(/spl Delta//sup 2/) messages. We prove this result for arbitrary node distributions and mobility patterns and also show that COB adapts asymptotically optimally to the mobility of the nodes. In our simulation experiments, we examine the network layer performance of COB, compare it with Dynamic Source Routing, and investigate the impact of the MAC layer on COB routing.

Both wavelength-division-multiplexing (WDM) networks with a ring architecture and WDM networks with a star architecture have been extensively studied as solutions to the ever increasing amount of traffic in the metropolitan area. Studies typically focus on either the ring or the star and significant advances have been made in the protocol design and performance optimization for the WDM ring and the WDM star, respectively. However, very little is known about the relative performance comparisons of ring and star networks. In this paper, we conduct a comprehensive comparison of a state-of-the-art WDM ring network with a state-of-the-art WDM star network. In particular, we compare time-slotted WDM ring networks (both single-fiber and dual-fiber) with tunable-transmitter and fixed-receiver (TT-FR) nodes and an arrayed-waveguide grating-based single-hop star network with tunable-transmitter and tunable-receiver (TT-TR) nodes. We evaluate mean aggregate throughput, relative packet loss, and mean delay by means of simulation for Bernoulli and self-similar traffic models for unicast traffic with uniform and hot-spot traffic matrices, as well as for multicast traffic. Our results quantify the fundamental performance characteristics of ring networks versus star networks and vice versa, as well as their respective performance limiting bottlenecks and, thus, provide guidance for directing future research efforts.