Equal cost multipath routing in IP networks

IP verkkojen palveluntarjoajat ja loppukäyttäjät vaativat yhä tehokkaampia ja parempilaatuisia palveluita, mikä vaatii tuotekehittäjiä tarjoamaan hienostuneempia liikennesuunnittelumenetelmiä verkon optimointia ja hallintaa varten. IS-IS ja OSPF ovat standardiratkaisut hoitamaan reititystä pienissä ja keskisuurissa pakettiverkoissa. Monipolkureititys on melko helppo ja yleispätevä tapa parantaa kuorman balansointia ja nopeaa suojausta tällaisissa yhden polun reititykseen keskittyvissä verkoissa. Tämä diplomityö kirjoitettiin aikana, jolloin monipolkureititys toteutettiin Tellabs-nimisen yrityksen 8600-sarjan reitittimiin. Tärkeimpiä kohtia monipolkureitityksen käyttöönotossa ovat lyhyimmän polun algoritmin muokkaukseen ja reititystaulun toimintaan liittyvät muutokset ohjaustasolla sekä kuormanbalansointialgoritmin toteutus reitittimen edelleenkuljetustasolla. Diplomityön tulokset sekä olemassa oleva kirjallisuus osoittavat, että kuormanbalansointialgoritmilla on suurin vaikutus yhtä hyvien polkujen liikenteen jakautumiseen ja että oikean algoritmin valinta on ratkaisevan tärkeää. Hajakoodaukseen perustuvat algoritmit, jotka pitävät suurimman osan liikennevuoista samalla polulla, ovat dominoivia ratkaisuja nykyisin. Tämän algoritmityypin etuna on helppo toteutettavuus ja kohtuullisen hyvä suorituskyky. Liikenne on jakautunut tasaisesti, kunhan liikennevuoiden lukumäärä on riittävän suuri. Monipolkureititys tarjoaa yksinkertaisen ratkaisun, jota on helppo konfiguroida ja ylläpitää. Suorituskyky on parempi kuin yksipolkureititykseen perustuvat ratkaisut ja se haastaa monimutkaisemmat MPLS ratkaisut. Ainoa huolehdittava asia on linkkien painojen asettaminen sillä tavalla, että riittävästi kuormantasauspolkuja syntyy.Increasing efficiency and quality demands of services from IP network service providers and end users drive developers to offer more and more sophisticated traffic engineering methods for network optimization and control. Intermediate System to Intermediate System and Open Shortest Path First are the standard routing solutions for intra-domain networks. An easy upgrade utilizes Equal Cost Multipath (ECMP) that is one of the most general solutions for IP traffic engineering to increase load balancing and fast protection performance of single path interior gateway protocols. This thesis was written during the implementation process of the ECMP feature of Tellabs 8600 series routers. The most important parts in adoption of ECMP are changes to shortest path first algorithm and routing table modification in the control plane and implementation of load balancing algorithm to the forwarding plane of router. The results of the thesis and existing literature prove, that the load balancing algorithm has the largest affect on traffic distribution of equal cost paths and the selection of the correct algorithm is crucial. Hash-based algorithms, that keep the traffic flows in the same path, are the dominating solutions currently. They provide simple implementation and moderate performance. Traffic is distributed evenly, when the number of flows is large enough. ECMP provides a simple solution that is easy to configure and maintain. It outperforms single path solutions and competes with more complex MPLS solutions. The only thing to take care of is the adjustment of link weights of the network in order to create enough load balancing paths

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Mobile Ad-Hoc Networks

Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: vehicular ad-hoc networks, security and caching, TCP in ad-hoc networks and emerging applications. It is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks