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An extensible markup language (XML) router topology-discovery control plane algorithm for creating an overlay network of XML routers is presented. This algorithm reduces processing requirements while delivering flexibility, scalability, and minimization of delays.

In wireless networks, important network functionalities such as power control, rate allocation, routing, and congestion control must be optimized in a coherent and integrated manner. In this work, an interference-limited wireless network is considered, whereby power control and routing variables are chosen to minimize the sum of link costs which depend on both link capacities and link flow rates. The necessary conditions for optimality are established. These conditions are sufficient for optimality if link cost functions are jointly convex, and imply Pareto optimality if link costs are strictly quasi-convex. Network algorithms based on the scaled gradient projection method, where power control and routing are performed on a node-by-node basis, are presented. For these algorithms, explicit scaling matrices and stepsizes are found which lead to more distributed implementation, and which guarantee fast convergence to a network configuration satisfying the optimality conditions, starting from any initial configuration with finite cost. Refinements of the algorithms for more accurate link capacity models are presented, and the results are extended to wireless networks where the physical-layer rate region is given by an arbitrary convex set. Finally, it is shown that the power control and routing algorithms can naturally be extended to incorporate congestion control. Index Terms--Congestion control, cross-layer optimization, distributed algorithms, multihop wireless networks, power control, routing.

The impact of Four-Wave-Mixing (FWM) is investigated using the proposed Assign Shortest Path First (ASPF) algorithm for wavelength assignment in Routing and Wavelength Assignment (RWA). Results show that ASPF algorithm indulges more FWM crosstalk in high optical channels for all input light power and low input power able to reduce he effect of FWM. The blocking probability due to FWM effects is approaching idea case when input power is less than or equal to 10 mW. Furthermore when the input light power is 15 mW, the blocking due to FWM crosstalk is extremely high. Thus, careful optical channel capacity, low FWM crosstalk, low input light power and a FWM-aware wavelength assignment algorithm are strongly desired for the accomplishment of efficient and high capacity WDM transparent optical network. Key words: Four wave mixing, shortest path algorithm, RWA, INTRODUCTION Most of the Routing and Wavelength Assignment (RWA) problems have been investigated under the assumption that the optical medium is an ideal one which can carry signals without any [...]

A hybrid wireless network is an extension to an infrastructure network, where a mobile host may connect to an access point (AP) using multihop wireless routes via other mobile hosts. The APs are configured to operate on one of multiple available channels. Mobile hosts and wireless routers can select their operating channels dynamically through channel switching. In this environment, we propose a routing protocol that finds routes to balance load among channels while maintaining connectivity. The protocol works with nodes equipped with a single network interface, which distinguishes our work with other multichannel routing protocols that require multiple interfaces per node. The protocol discovers multiple routes to multiple APs, possibly operating on different channels. Based on traffic load information, each node selects the 'best' route to an AP and synchronizes its channel with the AP. With this behavior, the channel load is balanced, removing hot spots and improving channel utilization. The protocol assures that every node has at least one route to an AP, where all intermediate nodes are operating on the same channel. Our simulation results show that the proposed protocol successfully adapts to changing traffic conditions and improves performance over a single-channel protocol and a multichannel protocol with no load balancing. Index Terms--Communication system routing, communication systems, load-balancing, multi-channel, multi-hop, protocols, routing.

Abstract: Ever since the Internet appeared, network elements, such as routers, have been enhanced with much functionality. They tend to increasingly integrate more services, such as support and security mechanisms, [...]

Abstract: Mobile agents can be seen as a new paradigm for distributed computing. One characteristic of mobile agents is their autonomy and pro-activity. This article present a framework designed on [...]

Abstract: Internet-based Mobile Ad Hoc Networking (MANET) is an emerging technology that supports self-organizing mobile networking infrastructures. This is expected to be of great use in commercial applications for the [...]

This paper presents a scalable routing protocol for very large and dense ad hoc networks. The scalability of ad hoc networks is becoming an important issue due to the increasing number of applications in a distributed environment, the great number of mobile nodes involved into communication and wide speed range in which the mobile nodes can move. It is important to offer scalability in terms of network size, traffic load and mobility speed. The proposed protocol, called Geo-LANMAR, inherits the same advantage of LANMAR protocol in terms of group motion support and traffic load scalability and it reflects also the behaviour of geo-routing protocols such as GPSR. Geo-LANMAR is based on the idea of Terminodes routing for the forwarding scheme: long-distance geo-forwarding and low-distance table-driven routing. Its updating scheme, instead, is similar to the Hazy Sighted Link State Routing (HSLS) through a spatial and time update rate differentiation: frequent update rate for short distance and lower update rate for long distance. Performance evaluation of Geo-LANMAR has been lead out and a comparison in terms of throughput, average end-to-end delay and control overhead has been conducted against other well-known protocols such as LANMAR, GPSR and AODV. Geo-LANMAR results scalable in terms of traffic load, mobility speed, number of nodes and number of groups. Keywords: Geo-LANMAR; Geo-routing; Scalable; HSLS; GPSR; Terminodes routing

Abstract: The Quality of Service Network on Chip (QNoC) is the most perferment solution that provides low latency transfers and power efficient System on Chip (SoC) interconnect. This study presents [...]

Abstract: Many Architectures of Internet routers, ATM and Ethernet switches have been proposed and analysed in literature. Theoretically reliable and valid solutions have been developed to achieve high performances, but [...]

In this paper we consider the problem of routing deterministic arriving jobs to parallel servers with deterministic (distinct) service times, where we assume that the arrival rate of the jobs [...]

Abstract: Wavelength Division Multiplexing (WDM) is a promising solution for data transport in future all-optical wide area networks. Such networks consist of fibers joined by dynamically controllable cross-connects which provide [...]

Byline: M.M. Hafizur Rahman, Susumu Horiguchi A Hierarchical Torus Network (HTN) is a 2D-torus network of multiple Basic Modules (BM), in which the BM are 3D-torus networks that are hierarchically interconnected for higher level networks. In this paper, we present a deadlock-free dimension-order routing using minimum number of Virtual Channels and evaluate the network's dynamic communication performance under the uniform traffic pattern by computer simulation and compare it with other contemporary conventional and hierarchical networks. We find that the dynamic communication performance of the HTN is better than that of the H3D-mesh, TESH, mesh, and torus networks. We also present the mapping of some primitive applications on the HTN. It is shown that the number of communication steps for various advanced applications mapping on the HTN is lower than that of those networks.