9 research outputs found
Cisco Systems
Label Switched Path (LSP) Ping/Traceroute Reply Mode Simplification draft-akiya-mpls-lsp-ping-reply-mode-simple-03 The Multiprotocol Label Switching (MPLS) Label Switched Path (LSP) Ping and Traceroute use the Reply Mode field to signal the method to be used in the MPLS echo reply. This document adds one value to the Reply Mode field to indicate reverse LSP. This document also adds an optional TLV which can carry ordered list of Reply Mode values. This document updates RFC4379
Segment Routing: a Comprehensive Survey of Research Activities, Standardization Efforts and Implementation Results
Fixed and mobile telecom operators, enterprise network operators and cloud
providers strive to face the challenging demands coming from the evolution of
IP networks (e.g. huge bandwidth requirements, integration of billions of
devices and millions of services in the cloud). Proposed in the early 2010s,
Segment Routing (SR) architecture helps face these challenging demands, and it
is currently being adopted and deployed. SR architecture is based on the
concept of source routing and has interesting scalability properties, as it
dramatically reduces the amount of state information to be configured in the
core nodes to support complex services. SR architecture was first implemented
with the MPLS dataplane and then, quite recently, with the IPv6 dataplane
(SRv6). IPv6 SR architecture (SRv6) has been extended from the simple steering
of packets across nodes to a general network programming approach, making it
very suitable for use cases such as Service Function Chaining and Network
Function Virtualization. In this paper we present a tutorial and a
comprehensive survey on SR technology, analyzing standardization efforts,
patents, research activities and implementation results. We start with an
introduction on the motivations for Segment Routing and an overview of its
evolution and standardization. Then, we provide a tutorial on Segment Routing
technology, with a focus on the novel SRv6 solution. We discuss the
standardization efforts and the patents providing details on the most important
documents and mentioning other ongoing activities. We then thoroughly analyze
research activities according to a taxonomy. We have identified 8 main
categories during our analysis of the current state of play: Monitoring,
Traffic Engineering, Failure Recovery, Centrally Controlled Architectures, Path
Encoding, Network Programming, Performance Evaluation and Miscellaneous...Comment: SUBMITTED TO IEEE COMMUNICATIONS SURVEYS & TUTORIAL
Étude et développement d'outils d'optimisation de gestion de services dans les réseaux MPLS
Beaucoup d'efforts se concentrent actuellement sur l'opération, administration et maintenance des réseaux MPLS, les fournisseurs de service ayant bien compris que pour générer des profits, les services doivent être gérés efficacement. Différents outils ont ainsi été développés par des équipes de recherche et par l'industrie, adressant un ou plusieurs aspects de la gestion de réseaux. Cependant, aucun outil ne permet à lui seul de visualiser la configuration d'un réseau hétérogène MPLS, avec ses applications principales, l'ingénierie de trafic et les VPN. En outre, la problématique de détection des pannes n'est abordée qu'en théorie.
Pour répondre à ce besoin, nous avons conçu un nouvel outil, permettant de fournir à l'administrateur une vue globale de son réseau MPLS via une interface Web. Il s'intègre avec un outil dédié à la qualité de service pour former QoS MPLS Assistant (QMA). La collecte d'informations est définie selon des standards établis, rendant QMA interopérable, fonctionnel quel que soit le constructeur des équipements. Par ailleurs, une méthode de surveillance de réseau a été mise au point, après étude et analyse des mécanismes actuellement proposés ou en cours de développement.
Lors du développement de cet outil, il a fallu tenir compte de l'écart constaté entre standards publiés et implémentations effectives dans les routeurs. De fait, certaines des fonctionnalités de QMA élaborées en théorie n'ont pu être concrètement mises en place. Pour autant, QMA est un outil riche, offrant à l'administrateur un moyen ergonomique et convivial de visualisation d'un réseau MPLS. Il a été testé avec succès sur une plateforme de tests de notre partenaire industriel Bell Canada.
Conçu avec une approche modulaire, pour faciliter son évolution, QMA pourra être repris dans le cadre d'un autre projet, et inclure de nouvelles fonctionnalités, voire même s'intégrer dans une solution professionnelle de gestion des réseaux
MPLS based recovery mechanisms
Multi-protocol label switching (MPLS) integrates the label swapping forwarding paradigm with network layer routing. To deliver reliable service, MPLS requires a set of procedures to provide protection of the traffic carried on different paths. This requires that the label switching routers (LSRs) support fault detection, fault notification, and fault recovery mechanisms, and that MPLS signaling supports the configuration of recovery. The purpose of this work is to evaluate the different recovery mechanisms proposed by the IETF, by literature study and simulation experiments
Concepção e implementação de experiências laboratoriais sobre MPLS
Mestrado em Engenharia Electrónica e TelecomunicaçõesO Multiprotocol Label Switching (MPLS) é um mecanismo de
transporte de dados, sob a forma de um protocolo agnóstico, com
grande potencial de crescimento e adequação. Opera na “Camada 2.5”
do modelo OSI e constitui um mecanismo de alto desempenho utilizado
nas redes de núcleo para transportar dados de um nó da rede para outro.
O sucesso do MPLS resulta do facto de permitir que a rede transporte
todos os tipos de dados, desde tráfego IP a tráfego da camada de
ligação de dados, devido ao encapsulamento dos pacotes dos diversos
protocolos, permitindo a criação de “links virtuais” entre nós distantes.
O MPLS pertence à família das “redes de comutação de pacotes”,
sendo os pacotes de dados associados a “etiquetas” que determinam o
seu encaminhamento, sem necessidade de examinar o conteúdo dos
próprios pacotes. Isto permite a criação de circuitos “extremo-aextremo”
através de qualquer tipo de rede de transporte e
independentemente do protocolo de encaminhamento que é utilizado.
O projecto do MPLS considera múltiplas tecnologias no sentido de
prestar um serviço único de transporte de dados, tentando
simultaneamente proporcionar capacidades de engenharia de tráfego e
controlo “out-of-band”, uma característica muito atraente para uma
implementação em grande escala. No fundo, o MPLS é uma forma de
consolidar muitas redes IP dentro de uma única rede.
Dada a importância desta tecnologia, é urgente desenvolver ferramentas
que permitam entender melhor a sua complexidade. O MPLS corre
normalmente nas redes de núcleo dos ISPs. No sentido de tornar o seu
estudo viável, recorreu-se nesta dissertação à emulação para
implementar cenários de complexidade adequada. Existem actualmente
boas ferramentas disponíveis que permitem a recriação em laboratório
de cenários bastante complicados.
Contudo, a exigência computacional da emulação é proporcional à
complexidade do projecto em questão, tornando-se rapidamente
impossível de realizar numa única máquina. A computação distribuída
ou a “Cloud Computing” são actualmente as abordagens mais
adequadas e inovadoras apara a resolução deste problema.
Esta dissertação tem como objectivo criar algumas experiências em
laboratório que evidenciam aspectos relevantes da tecnologia MPLS,
usando para esse efeito um emulador computacional, o Dynamips,
impulsionado por generosas fontes computacionais disponibilizadas
pela Amazon ec2. A utilização destas ferramentas de emulação permite
testar cenários de rede e serviços reais em ambiente controlado,
efectuando o debugging das suas configurações e optimizando o seu
desempenho, antes de os colocar em funcionamento nas redes em
operação.The Multiprotocol Label Switching (MPLS) is a highly scalable and
agnostic protocol to carry network data.
Operating at "Layer 2.5" of the OSI model, MPLS is an highperformance
mechanism that is used at the network backbone for
conveying data from one network node to the next.
The success of MPLS results from the fact that it enables the network to
carry all kinds of traffic, ranging from IP to layer 2 traffic, since it
encapsulates the packets of the diverse network protocols, allowing the
creation of "virtual links" between distant nodes.
MPLS belongs to the family of packet switched networks, where labels
are assigned to data packets that are forwarded based on decisions that
rely only on the label contents, without the need to examine the packets
contents. This allows the creation of end-to-end circuits across any type
of transport medium, using any protocol.
The MPLS design takes multiform transport technologies into account to
provide a unified data-carrying service, attempting simultaneously to
preserve traffic engineering and out-of-band control, a very attractive
characteristic for large-scale deployment. MPLS is the way to
consolidate many IP networks into a single one. Due to this obvious
potential, it is urgent to develop means and tools to better understand its
functioning and complexity.
MPLS normally runs at the backbone of Service Providers networks,
being deployed across an extensive set of expensive equipment. In order
to turn the study of MPLS feasible, emulation was considered as the best
solution. Currently, there are very good available tools to recreate, in a
lab environment, quite complicated scenarios.
However, the computational demand of the emulation is proportional to
the complexity of the project, becoming quickly unfeasible in a single
machine.
Fortunately, distributed computing or Cloud computing are suitable and
novel approaches to solve this computation problem.
So, this work aims to create some lab experiments that can
illustrate/demonstrate relevant aspects of the MPLS technology, using the
Dynamips emulator driven by the computational resources that were
made available by the Amazon ec2 cloud computing facilities. The
utilization of these emulation tools allows testing real networks and
service scenarios in a controlled environment, being able to debug their
configurations and optimize their performance before deploying them in
real operating networks
Recommended from our members
Intelligent based Packet Scheduling Scheme using Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) Technology for 5G. Design and Investigation of Bandwidth Management Technique for Service-Aware Traffic Engineering using Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) for 5G
Multi-Protocol Label Switching (MPLS) makes use of traffic engineering (TE)
techniques and a variety of protocols to establish pre-determined highly
efficient routes in Wide Area Network (WAN). Unlike IP networks in which
routing decision has to be made through header analysis on a hop-by-hop
basis, MPLS makes use of a short bit sequence that indicates the forwarding
equivalence class (FEC) of a packet and utilises a predefined routing table to
handle packets of a specific FEC type. Thus header analysis of packets is not
required, resulting in lower latency. In addition, packets of similar
characteristics can be routed in a consistent manner. For example, packets
carrying real-time information can be routed to low latency paths across the
networks. Thus the key success to MPLS is to efficiently control and distribute
the bandwidth available between applications across the networks.
A lot of research effort on bandwidth management in MPLS networks has
already been devoted in the past. However, with the imminent roll out of 5G,
MPLS is seen as a key technology for mobile backhaul. To cope with the 5G
demands of rich, context aware and multimedia-based user applications, more
efficient bandwidth management solutions need to be derived.
This thesis focuses on the design of bandwidth management algorithms, more
specifically QoS scheduling, in MPLS network for 5G mobile backhaul. The
aim is to ensure the reliability and the speed of packet transfer across the
network. As 5G is expected to greatly improve the user experience with
innovative and high quality services, users’ perceived quality of service (QoS)
needs to be taken into account when deriving such bandwidth management
solutions. QoS expectation from users are often subjective and vague. Thus
this thesis proposes the use of fuzzy logic based solution to provide service aware and user-centric bandwidth management in order to satisfy
requirements imposed by the network and users.
Unfortunately, the disadvantage of fuzzy logic is scalability since dependable
fuzzy rules and membership functions increase when the complexity of being
modelled increases. To resolve this issue, this thesis proposes the use of neuro-fuzzy to solicit interpretable IF-THEN rules.The algorithms are
implemented and tested through NS2 and Matlab simulations. The
performance of the algorithms are evaluated and compared with other
conventional algorithms in terms of average throughput, delay, reliability, cost,
packet loss ratio, and utilization rate.
Simulation results show that the neuro-fuzzy based algorithm perform better
than fuzzy and other conventional packet scheduling algorithms using IP and
IP over MPLS technologies.Tertiary Education Trust Fund (TETFUND
An Introduction to Computer Networks
An open textbook for undergraduate and graduate courses on computer networks
Analyse und Optimierung von Hybriden Software-Defined Networks
Hybrid IP networks that use both control plane paradigms - distributed and centralized - promise the best of two worlds: programmability and flexible control of Software-Defined Networking (SDN), and at the same time the reliability and fault tolerance of distributed routing protocols like Open Shortest Path First (OSPF). Hybrid SDN/OSPF networks typically deploy OSPF to assure care-free operation of best effort traffic, while SDN can control prioritized traffic. This "ships-passing-in-the-night" approach, where both control planes are unaware of each other's configurations, only require hybrid SDN/OSPF routers that can participate in the domain-wide legacy routing protocol and additionally connect to a central SDN controller. This mode of operation is however known for a number of challenges in operational networks, including those related to network failures, size of forwarding tables, routing convergence time, and the increased complexity of network management.
There are alternative modes of hybrid operation that provide a more holistic network control paradigm, either through an OSPF-enabled SDN controller, or a common network management system that allows the joint monitoring and configuration of both control planes, or via the partitioning of the legacy routing domain with SDN border nodes. The latter mode of operation offers to some extent to steer the working of the legacy routing protocol inside the sub-domains, which is new. The analysis, modeling, and evaluative comparison of this approach called SDN Partitioning with other modes of operation is the main contribution of this thesis.
This thesis addresses important network planning tasks in hybrid SDN/OSPF networks and provides the according mathematical models to optimize network clustering, capacity planning, SDN node placement, and resource provisioning for a fault tolerant operation. It furthermore provides the mathematical models to optimize traffic engineering, failure recovery, reconfiguration scheduling, and traffic monitoring in hybrid SDN/OSPF networks, which are vital network operational tasks.Hybride IP-Netzwerke, die beide Control-Plane-Paradigmen einsetzen - verteilt und zentralisiert - versprechen das Beste aus beiden Welten: Programmierbarkeit und flexible Kontrolle des Software-Defined Networking (SDN) und gleichzeitig die Zuverlässigkeit und Fehlertoleranz von verteilten Routingprotokollen wie Open Shortest Path First (OSPF). Hybride SDN/OSPF-Netze nutzen typischerweise OSPF für die wartungsarme Bedienung des Best-Effort-Datenverkehrs, während SDN priorisierte Datenströme kontrolliert. Bei diesem Ansatz ist beiden Kontrollinstanzen die Konfiguration der jeweils anderen unbekannt, wodurch hierbei hybride SDN/OSPF Router benötigt werden, die am domänenweiten Routingprotokoll teilnehmen können und zusätzlich eine Verbindung zu einem SDN-Controller herstellen. Diese Arbeitsweise bereitet jedoch bekanntermaßen eine Reihe von Schwierigkeiten in operativen Netzen, wie zum Beispiel die Reaktion auf Störungen, die Größe der Forwarding-Tabellen, die benötigte Zeit zur Konvergenz des Routings, sowie die höhere Komplexität der Netzwerkadministration.
Es existieren alternative Betriebsmodi für hybride Netze, die einen ganzheitlicheren Kontrollansatz bieten, entweder mittels OSPF-Erweiterungen im SDN-Controller, oder mittels eines übergreifenden Netzwerkmanagementsystems, dass das Monitoring und die Konfiguration aller Netzelemente erlaubt. Eine weitere Möglichkeit stellt das Clustering der ursprünglichen Routingdomäne in kleinere Subdomänen mittels SDN-Grenzknoten dar. Dieser neue Betriebsmodus erlaubt es zu einem gewissen Grad, die Operationen des Routingprotokolls in den Subdomänen zu steuern. Die Analyse, Modellierung und die vergleichende Evaluation dieses Ansatzes mit dem Namen SDN-Partitionierung und anderen hybriden Betriebsmodi ist der Hauptbeitrag dieser Dissertation.
Diese Dissertation behandelt grundlegende Fragen der Netzplanung in hybriden SDN/OSPF-Netzen und beinhaltet entsprechende mathematische Modelle zur Optimierung des Clusterings, zur Kapazitätsplanung, zum Platzieren von SDN-Routern, sowie zur Bestimmung der notwendigen Ressourcen für einen fehlertoleranten Betrieb. Desweiteren enthält diese Dissertation Optimierungsmodelle für Traffic Engineering, zur Störungsbehebung, zur Ablaufplanung von Konfigurationsprozessen, sowie zum Monitoring des Datenverkehrs in hybriden SDN/OSPF-Netzen, was entscheidende Aufgaben der Netzadministration sind