Implementation and performance measurements of QoS routing extensions to OSPF

Apostolopoulos, George; Guérin, Roch; Kamat, S.

doi:10.1109/infcom.1999.751454

Cited by 93 publications

(53 citation statements)

References 9 publications

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“…However, none has addressed the mechanism of the protocol in details. Most of the QoS routing protocols were proposed in a form of an extension to the existing routing protocol, such as OSPF [MOY94], e.g., [APOS99a], [APOS99b], and [GUER97], and BGP [REKH95], e.g., [XIAO02]. The extensions to the existing protocol have many benefits.…”

Section: Qos Routing Protocolsmentioning

confidence: 99%

A Clustering-Based Selective Probing Framework to Support Internet Quality of Service Routing

Jariyakul

Znati

2005

Distributed Computing – IWDC 2005

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The advent of the multimedia applications has triggered widespread interest in QoS supports. Two Internet-based QoS frameworks have been proposed: Integrated Services (IntServ) and Differentiated Services (DiffServ). IntServ supports service guarantees on a per-flow basis. The framework, however, is not scalable due to the fact that routers have to maintain a large amount of state information for each supported flow. DiffServ was proposed as an alternate solution to address the lack of scalability of the IntServ framework. DiffServ uses class-based service differentiation to achieve aggregate support for QoS requirements. This approach eliminates the need to maintain per-flow states on a hop-by-hop basis and reduces considerably the overhead routers incur in forwarding traffic.Both IntServ and DiffServ frameworks focus on packet scheduling. As such, they decouple routing from QoS provisioning. This typically results in inefficient routes, thereby limiting the ability of the network to support QoS requirements and to manage resources efficiently. The goal of this thesis is to address this shortcoming. We propose a scalable QoS routing framework to identify and select paths that are very likely to meet the QoS requirements of the underlying applications. The tenet of our approach is based on seamlessly integrating routing into the DiffServ framework to extend its ability to support QoS requirements. Scalability is achieved using selective probing and clustering to reduce signaling and routers overhead.The major contributions of this thesis are as follows: First, we propose a scalable routing architecture that supports QoS requirements. The architecture seamlessly integrates the QoS traffic requirements of the underlying applications into a DiffServ framework. Second, we propose a new delay-based clustering method, referred to as d-median. The proposed clustering method groups Internet nodes into clusters, whereby nodes in the same cluster exhibit equivalent delay characteristics. Each cluster is represented by anchor node. Anchors use selective probing to estimate QoS parameters and select appropriate paths for traffic forwarding.A thorough study to evaluate the performance of the proposed d-median clustering algorithm is conducted. The results of the study show that, for power-law graphs such as the Internet, the d-median clustering based approach outperforms the set covering method commonly proposed in the literature. The study shows that the widely used clustering methods, such as set covering or k-median, are inadequate to capture the balance between cluster sizes and the number of clusters. The results of the study also show that the proposed clustering method, applied to power-law graphs, is robust to changes in size and delay distribution of the network. Finally, the results suggest that the delay bound input parameter of the d-median scheme should be no less than 1 and no more than 4 times of the average delay per one hop of the network. This is mostly due to the weak hierarchy of the Internet resulting fr...

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Section: Qos Routing Protocolsmentioning

confidence: 99%

A Clustering-Based Selective Probing Framework to Support Internet Quality of Service Routing

Jariyakul

Znati

2005

Distributed Computing – IWDC 2005

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“…Finally, we discuss issues that arose during the implementation effort and present some measurement based results on the overhead that the QoS extensions impose on a QoS capable router and a network of QoS routers. For further details on the implementation study, the reader is referred to [AGK99]. Additional performance evaluation based on simulations can be found in [AGKT98].…”

Section: A Reference Implementation Based On Gatedmentioning

confidence: 99%

“…The topology used in the measurements was built by replicating a basic building block consisting of four routers connected with transit networks in a rectangular arrangement. The details of the topology and the measurements can be found in [AGK99]. The system running the GateD software was an IBM IntelliStation Z Pro with a Pentium Pro processor at 200 MHz, 64 MBytes or real memory, running FreeBSD 2.2.5-RELEASE and GateD 4.…”

Section: Bandwidth and Processing Overhead Of Qos Routingmentioning

confidence: 99%

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QoS Routing Mechanisms and OSPF Extensions

Apostolopoulos¹,

Kama²,

Williams³

et al. 1999

Self Cite

381

213

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This memo describes extensions to the OSPF [Moy98] protocol to support QoS routes. The focus of this document is on the algorithms used to compute QoS routes and on the necessary modifications to OSPF to support this function, e.g., the information needed, its format, how it is distributed, and how it is used by the QoS path selection process. Aspects related to how QoS routes are established and managed are also briefly discussed. The goal of this document is to identify a framework and possible approaches to allow deployment of QoS routing capabilities with the minimum possible impact to the existing routing infrastructure.In addition, experience from an implementation of the proposed extensions in the GateD environment [Con], along with performance measurements is presented.

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“…OSPF, BGP) [3,5,15,17,49]. Several recent studies have acknowledged the need for scalable QoS routing solutions [4,11,27,29,48] and have given the stimulus for a number of proposals on how to integrate QoS routing into a Differentiated Services (DiffServ) framework [21,24,43].…”

Section: Motivationmentioning

confidence: 99%

Algorithms and protocols for stateless constrained-based routing

Zhang

Krunz

2003

Computer Communications

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Quality of service (QoS) routing has generally been addressed in the context of reservation-based network services (e.g. ATM, IntServ), which require explicit (out of band) signaling of reservation requests and maintenance of per-flow state information. It has been recognized that the processing of per-flow state information poses scalability problems, especially at core routers. To remedy this situation, in this paper we introduce an approach for stateless QoS routing in IP networks that assumes no support for signaling or reservation from the network. Instead, our approach makes use of the currently unused two bits in the DiffServ (DS) byte of the IP packet header. Simple heuristics are used to identify a low-cost delay-constrained path. These heuristics essentially divide the end-to-end path into at most two 'superedges' that are connected by a 'relay node'. Routers that lie on the same superedge use either the cost metric or the delay metric (but not both) to forward the packet. Standard hop-by-hop forwarding is performed with respect to either metric. Two different approaches are presented for implementing the relay-based forwarding. In the first approach, a probing protocol is used to identify the relay node and the routing metrics of the superedges. Tunneling and packet encapsulation are then used to forward packets from the source node to the relay node and then from the relay node to the destination node. The second approach does not require probing, but instead relies on the time-to-live (TTL) field in the header of the IP packet. Simulations are presented to evaluate the cost performance of the various approaches. q

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Implementation and performance measurements of QoS routing extensions to OSPF

Cited by 93 publications

References 9 publications

A Clustering-Based Selective Probing Framework to Support Internet Quality of Service Routing

A Clustering-Based Selective Probing Framework to Support Internet Quality of Service Routing

QoS Routing Mechanisms and OSPF Extensions

Algorithms and protocols for stateless constrained-based routing

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