49 research outputs found
Recovery modeling in MPLS networks
Transmission of QoS based traffic over packet switched network typically requires resource reservation or differentiated treatment to guarantee an acceptable level of performance. But it is also essential to bound the disruption caused by failure of nodes or links for a real time traffic to a limit that is acceptable by the application. In this paper, a simulation platform models the impact of the MPLS recovery/protection schemes on the QoS traffic parameters including disruption time and number of out of order packets arriving at the destination. The simulation considers measures to alleviate drawbacks caused by recovery process
Multi-Objective Routing Optimization for Multiple Level Priority and Preemption in Multi-Tiered Networks
This thesis explores techniques for improving the Quality of Service (QoS) driven routing of IP traffic in a Network Centric Military Communications System within an HC3 (High Capacity Communications Capability) tiered topology. In this specialized network various routing algorithms, including traditional, QoS-constrained search-based, and heuristic approaches, were evaluated. An automatic system for the probabilistic generation of appropriate networks and traffic was created for Monte Carlo simulation of the systems and testing of the various routing algorithms. A new algorithm we propose, based upon a hiercharical decomposition of routes about the minimum distance routes, is described and tested. These results provide both insight into this problem and demonstrate the possibility of highly optimized solutions without exhaustive search
An Efficient Routing Method for Protection Data Flow in the MPLS Network
تقدم هذه الورقة طريقة فعالة لإعادة توجيه حركة المرور في شبكة الMPLS وذلك عندما يحدث خطأ في المسار الناقل. و قد تم تصميم هذه الطريقة لمعالجة كل من الأخطاء الفردية والمتعددة استنادا إلى تقنيات الحماية وإعادة التوجيه. حيث تؤدي الطريقة المقترحة إلى خسارة أقل للحزم (decrease packet loss)، ولها نسبة توصيل أفضل للخدمة (PDR)، وتحسين في الإنتاجية (Throughput)، وتحسين في وصول حزم البيانات بشكل منتظم (packet order). تم محاكاة الطريقة المقترحة باستخدام محاكي الشبكة (NS2) الإصدار 2.34 وقد أظهرت نتائج المحاكاة أن الطريقة المقترحة تحسن بشكل كبير من أداء الشبكة بالمقارنة مع الأساليب و الطرق الموجودة في الأبحاث العلمية المشابهة.
الكلمات المفتاحية: شبكة الـ MPLS, عمل الـ Link, حماية البديل, إعادة التوجيه, محاكاه الشبكة.This paper presents an efficient method for rerouting traffic in the Multiprotocol Label Switching (MPLS) network, when a fault occurs in the working link. The method has been designed to handle both single and multiple faults based on the protection switching and rerouting techniques. The proposed method leads to less packets loss, has better Packet Delivery Ratio (PDR), good throughput and eliminates packet disorder. The proposed method has been simulated using the Network Simulator (NS2) version 2.34 and the simulation results have shown that the proposed method significantly improves the network performance in comparison to similar existing methods.
Keywords: MPLS network, Working link, Protection switching, Rerouting, Network simulator
QoS-aware Mobility Management in IP-based Communication Networks
Der allgegenwärtige Zugang zu Informationen, jederzeit und überall, ist ein
wichtiges Merkmal künftiger All-IP-Mobilfunktnetze, die verschiedene
Systeme miteinander verbinden, dabei dynamischer und flexibler sein
werden. Der Einsatz dieser Netze erfordert es jedoch, viele
Herausforderungen zu überwinden. Eine der wichtigsten im Rahmen dieser
Arbeit, ist die Frage, wie Quality of Service (QoS) Eigenschaften in
solchen hoch dynamischen, mobilen Umgebungen zu garantieren sind. Bekanntermaßen beeinflusst die Mobilität von Mobilknoten (MN) die Dienstgüte in mobilen Netzen, da QoS-Parameters für
die Ende-zu-Ende-Kommunikation vereinbart werden. Daher müssen Lösungen
entwickelt werden, die nahtlose Mobilität, bei gleichzeitigen QoS-Garantien
nach Handoffs, unterstützen. Diese Herausforderung ist das Hauptziel der
vorliegenden Dissertation, die einen umfassenden Überblick über die
bestehenden Mobilitäts- und QoS-Managment-Lösungen in IP-basierten Netzen
liefert, gefolgt von einem Einblick in Methoden zur Kopplung von
Mobilitätsmanagement und QoS-Lösungen. Nach Betrachtung der Vor- und
Nachteile bestehender Ansätze, kommt die Dissertation zu dem Schluss, dass
hybride Strategien vielversprechend sind und zu praktikablen Lösungen
weiterentwickelt werden können, die sowohl Mobilitäts- als auch
QoS-Anforderungen auf effiziente Weise,in allen zukünftigen IP-Mobilfunknetzen erfüllen können. Auf dieser Grundlage schlägt die Dissertation ein neues Hybrid-Protokoll, genannt
"QoS-aware Mobile IP Fast Authentication Protocol" (QoMIFA), vor. Unser
Vorschlag integriert MIFA als Mobilitäts-Management-Protokoll mit RSVP als
QoS Reservierungsprotokoll. MI-FA wird aufgrund seiner Fähigkeit zu
schnellen, sicheren und robusten Handoffs gewählt. RSVP hingegen dient als
Standardlösung zur Bereitstellung von QoS in bestehenden IP-basierten
Netzen. Unter Einhaltung der Hybrid-Architektur wird RSVP um ein neues
Objekt, genannt "Mobility Object" erweitert, welches
MIFA-Kontrollnachrichten kapselt. Nach der Spezifikation des neuen
Vorschlags, bewertet die Dissertation auch seine Leistung im Vergleich zu
dem bekannten "Simple QoS Signaling Protocol" (Simple QoS), mittels
Simulationsstudien, modelliert mit dem "Network Simluator 2" (NS2). In der
Auswertung werden der Einflusses der Netzwerklast und der Geschwindigkeit
des Mobilknotens untersucht. Die hierzu verwendeten Leistungsparameter
umfassen die Ressourcen-Reservierungs-Latenz, die Anzahl verlorener Pakete
pro Handoff, die Anzahl der, vor Abschluss der Reservierung, mit
Best-Effort-Eigenschaften übertragenen Pakete pro Handoff und die
Wahrscheinlichkeit von Verbindungsabbrüchen. Unsere mittels Simulation
erzielten Ergebnisse zeigen, dass QoMIFA schnelle und nahtlose Handoffs mit
schneller Ressourcenreservierung nach Handoffs kombinieren kann. Unter
Berücksichtigung des Einflusses der Netzwerklast, ist nachweisbar, dass
QoMIFA eine besser Leistung als Simple QoS in allen untersuchten Szenarien
mit geringer, mittlerer und hoher Last erreicht. Bei Betrachtung des
Einflusses der Bewegungsgeschwindigkeit des Mobilknotens auf die Leistung,
lassen sich unter beiden Protokollen Ping-Pong-Effekte beobachten, welche
zu höheren Ressourcen-Reservierungs-Latenzen, mehr verlorenen Paketen und
mehr Best-Effort-Paketen pro Handoff bei geringeren Geschwindigkeiten
führen. Der stärkste Einfluss dieser Pinp-Pong-Effekte ist jeweils bei 3
km/h zu beobachten. Allerdings verhält sich QoMIFA unter allen untersuchten
Bewegungsgeschwindigkeiten besser als Simple QoS und kann Mobilknoten auch
bei hohen Geschwindigkeiten bedienen. In Anschluss an die
simulationsgestützte Evaluierung, schätzt die Dissertation die
Signalisierungskosten beider Protokolle unter Betrachtung der Kosten für
Ortslokalise-rung und Paketzustellung. Im Ergebnis erreicht QoMIFA die
zuvor genannten Leistungsverbesserungen auf Kosten von größeren
Ortslokalisierungskosten und leicht höherer Paketzustellungskosten.Ubiquitous access to information anywhere, anytime and anyhow is an
important feature of future all-IP mobile communication networks, which
will interconnect various systems and be more dynamic and flexible. The
deployment of these networks, however, requires overcoming many challenges.
One of the main challenges of interest for this work is how to provide
Qual-ity of Service (QoS) guarantees in such highly dynamic mobile
environments.As known, mobility of Mobile Nodes (MNs) affects the QoS in
mobile networks since QoS parameters are made for end-to-end
communications. Therefore, it is a challenge to develop new solutions
capable of supporting seamless mobility while simultaneously providing QoS
guarantees after handoffs. Addressing this challenge is the main objective
of this dissertation, which provides a comprehensive overview of mobility
management solutions and QoS mech-anisms in IP-based networks followed by
an insight into how mobility management and QoS solutions can be coupled
with each other. Following the highlight of the state of art along with the
pros and cons of existing approaches, the dissertation concludes that
hybrid strategies are promising and can be further developed to achieve
solutions that are capable of simultaneous-ly supporting mobility and QoS,
simple from the implementation point of view, efficient and applicable to
future all-IP mobile communication networks.Based on this, the dissertation
proposes a new hybrid proposal named QoS-aware Mobile IP Fast
Authentication Protocol (QoMIFA). Our proposal integrates MIFA as a
mobility man-agement protocol with RSVP as a QoS reservation protocol. MIFA
is selected due to its capa-bility of the provision of fast, secure and
robust handoffs, while RSVP is chosen because it presents the standard
solution used to support QoS in existing IP-based networks. The hybrid
architecture is retained by introducing a new object, called “mobility
object”, to RSVP in or-der to encapsulate MIFA control messages.Following
the specification of the new proposal, the dissertation also evaluates its
perfor-mance compared to the well-known Simple QoS signaling protocol
(Simple QoS) by means of simulation studies modeled using the Network
Simulator 2 (NS2). The evaluation compris-es the investigation of the
impact of network load and MN speed. The performance measures we are
interested in studying comprise the resource reservation latency, number of
dropped packets per handoff, number of packets sent as best-effort per
handoff until the reservation is accomplished and probability of dropping
sessions. Our simulation results show that QoMIFA is capable of achieving
fast and smooth handoffs in addition to its capability of quickly
re-serving resources after handoffs. Considering the impact of network
load, QoMIFA outper-forms Simple QoS in all studied scenarios (low- ,
middle- and high-loaded scenarios). With respect to the impact of MN speed,
it can be observed that the impact of ping-pong effects is seen with both
protocols and results in higher resource reservation latency, more dropped
packets per handoff and more best-effort packets per handoff at low speeds
than at higher ones. The worst impact of ping-pong effects is seen at a
speed of 3 km/h when employing QoMIFA and Simple QoS, respectively.
However, QoMIFA remains performing significantly better than Simple QoS
under all studied MN speeds and can even properly serve MNs mov-ing at high
speeds.Following the simulative evaluation, the dissertation estimates the
signaling cost of both stud-ied protocols with respect to the location
update and packet delivery cost. Our results show that QoMIFA achieves the
above mentioned performance improvements at the cost of greater location
update cost and slightly higher packet delivery cost than Simple QoS
Single fault tolerance method for protection data flow in the MPLS network
This paper presents efficient methods for rerouting traffic in the Multiprotocol Label Switching (MPLS) network, when a fault occurs in the working link. The proposed methods have been designed to handle single fault based on the protection switching and rerouting techniques. In this paper three algorithms are developed for fault recovery in the MPLS network based on ingress LSR, alert LSR and core LSR. The proposed methods have been simulated using the Network Simulator (NS2) and the simulation results show that the proposed methods significantly improve the network performance in comparison to similar existing methods
Intra-domain mobility management
Mobility supporting protocols are designed to provide connectivity of mobile nodes from any point of attachment to the Internet. Fast handoff, low signaling overhead and packet loss are the key factors to be addressed in designing a mobility management protocol. This work proposes Intra Domain Mobility Management (IDMM) protocol, based on micro-mobility concept. The protocol implements an efficient tracking mechanism for locating the mobile nodes and ensures that their movements remain transparent to communicating nodes. The protocol is designed with the hierarchical tree topology in mind that allows for low cost solution and efficient management. The optimized routing enables fast delivery of packets to the mobile node in the micro-mobility domain. IDMM is implemented using Network Simulator (ns2) tools. Packet loss, throughput, delay in the network and traffic overhead due to location management are studied. The comparison with major mobility protocols such as Mobile IP and Cellular IP is done to demonstrate the performance of IDMM under high frequency of roaming
Quality of service and mobility management in IP-based radio access networks
Master'sMASTER OF ENGINEERIN
Dynamic bandwidth management to maximize user satisfaction degree on multiple MPLS paths
Master'sMASTER OF ENGINEERIN