Routing issues for dynamic networks

The routing is one very important function implemented in computer communication networks. It collects information about optimal paths within a network;The purpose of this dissertation is to study the routing function in large networks which are characterized by frequent topological changes. The study focuses on constructing routing protocols with some desirable properties such as distributed computation, adaptation to flow variations within the network, failsafe against arbitrary topological changes, loop-free route tables for all destinations at all times, bounded values for variables, and fast recovery from topological changes;At present, most routing protocols use the next-node routing technique, a technique in which each node keeps only the next node identification for a particular destination. A different type of routing scheme provided in some protocol standards is called source routing. A source routing protocol builds complete paths from a source to all destinations in the network. Several source routing algorithms are derived with desirable properties;Most distributed routing algorithms use one or more variables to store unbounded values such as update cycle numbers. Distributed routing protocols with bounded update cycle numbers are proposed. The proposed protocols possess desirable properties and are obtained by applying the sliding window idea for flow control in networks to the routing protocols which employ unbounded update cycle numbers;How fast an algorithm provides optimal paths from every node to every other node in a network after a topological change is an important consideration in the design of routing algorithms. Several algorithms for achieving shortest paths to all destinations in the network with improved recovery speed from topological changes are presented

Survey of Routing Algorithms for Computer Networks

This thesis gives a general discussion of routing for computer networks, followed by an overview of a number of typical routing algorithms used or reported in the past few years. Attention is mainly focused on distributed adaptive routing algorithms for packet switching (or message switching) networks. Algorithms for major commercial networks (or network architectures) are reviewed as well, for the convenience of comparison

Distributed decision and communication problems, final report

"June 1987." Title from cover. "MIT OSP no. 85552."Includes bibliographical references.Funded by the Office of Naval Research. N00014-77-C-0532 NR 041-519.prepared by Michael Athans; submitted to J. Randolph Simpson, Code 111SP, Office of Naval Research

Optimal distributed routing for virtual line-switched data networks

Bibliography: p. 35."September 1978."Supported by the Advanced Research Project Agency (monitored by ONR) under Contract no. N00014-75-C-1183Adrian Segall

Implementación de un sistema SDN para la movilidad en redes OMNIRAN

This document details all the information needed to understand and test distributed mobility management using the SDN paradigm. This project stars by an analysis of the mobility problem in dense networks. Traditionally mobility has been managed with hierarchical approaches extending the current mobility protocols. But thinking in the future evolution of the network into dense environments some scalability problems appear. The traditional centralized elements may not be able to handle all the traffic in the network and bottlenecks appear at the Mobility Anchors. Nowadays, the problems related to scalability are mostly resolved with hardware upgrades, but in dense environments this couldn’t be enough and surely it would be quite expensive. To find a solution to this problem the IETF has chartered the Distributed Mobility Management (DMM) Group.This project focus on implementing a DMM-based mobility solution designed within the EU FP7 CROWD project. Once the analysis of the problem ended and the requirements of the theoretical solution were defined, we developed all the necessary elements to physically build a distributed network using SDN to manage layer 2 and layer 3.The entities of the network are defined by the CROWD projectin its related publications[9][10]. These districts were run using an SDN implementation called OpenFlow. With all the elements developed we proceed to perform the necessary tests in order to evaluate the distributed mobility management as a solution. This document explains the full design, execution and validationprocesses. Finally all the measurements and statistical data are detailed in order to have an approximation of the services that could achieve the developed network.Ingeniería Telemátic

Self-stabilizing cluster routing in Manet using link-cluster architecture

We design a self-stabilizing cluster routing algorithm based on the link-cluster architecture of wireless ad hoc networks. The network is divided into clusters. Each cluster has a single special node, called a clusterhead that contains the routing information about inter and intra-cluster communication. A cluster is comprised of all nodes that choose the corresponding clusterhead as their leader. The algorithm consists of two main tasks. First, the set of special nodes (clusterheads) is elected such that it models the link-cluster architecture: any node belongs to a single cluster, it is within two hops of the clusterhead, it knows the direct neighbor on the shortest path towards the clusterhead, and there exist no two adjacent clusterheads. Second, the routing tables are maintained by the clusterheads to store information about nodes both within and outside the cluster. There are two advantages of maintaining routing tables only in the clusterheads. First, as no two neighboring nodes are clusterheads (as per the link-cluster architecture), there is no need to check the consistency of the routing tables. Second, since all other nodes have significantly less work (they only forward messages), they use much less power than the clusterheads. Therefore, if a clusterhead runs out of power, a neighboring node (that is not a clusterhead) can accept the role of a clusterhead. (Abstract shortened by UMI.)

Architecture for Cognitive Networking within NASAs Future Space Communications Infrastructure

Future space mission concepts and designs pose many networking challenges for command, telemetry, and science data applications with diverse end-to-end data delivery needs. For future end-to-end architecture designs, a key challenge is meeting expected application quality of service requirements for multiple simultaneous mission data flows with options to use diverse onboard local data buses, commercial ground networks, and multiple satellite relay constellations in LEO, MEO, GEO, or even deep space relay links. Effectively utilizing a complex network topology requires orchestration and direction that spans the many discrete, individually addressable computer systems, which cause them to act in concert to achieve the overall network goals. The system must be intelligent enough to not only function under nominal conditions, but also adapt to unexpected situations, and reorganize or adapt to perform roles not originally intended for the system or explicitly programmed. This paper describes architecture features of cognitive networking within the future NASA space communications infrastructure, and interacting with the legacy systems and infrastructure in the meantime. The paper begins by discussing the need for increased automation, including inter-system collaboration. This discussion motivates the features of an architecture including cognitive networking for future missions and relays, interoperating with both existing endpoint-based networking models and emerging information-centric models. From this basis, we discuss progress on a proof-of-concept implementation of this architecture as a cognitive networking on-orbit application on the SCaN Testbed attached to the International Space Station

Implicit Simulations using Messaging Protocols

A novel algorithm for performing parallel, distributed computer simulations on the Internet using IP control messages is introduced. The algorithm employs carefully constructed ICMP packets which enable the required computations to be completed as part of the standard IP communication protocol. After providing a detailed description of the algorithm, experimental applications in the areas of stochastic neural networks and deterministic cellular automata are discussed. As an example of the algorithms potential power, a simulation of a deterministic cellular automaton involving 10^5 Internet connected devices was performed.Comment: 14 pages, 3 figure