Browse Prior Art Database

QoS Routing Mechanisms and OSPF Extensions (RFC2676)

IP.com Disclosure Number: IPCOM000003267D
Original Publication Date: 1999-Aug-01
Included in the Prior Art Database: 2019-Feb-11
Document File: 50 page(s) / 74K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

G. Apostolopoulos: AUTHOR [+5]

Related Documents

10.17487/RFC2676: DOI

Abstract

This memo describes extensions to the OSPF 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. This memo defines an Experimental Protocol for the Internet community.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 4% of the total text.

Network Working Group G. Apostolopoulos Request for Comments: 2676 D. Williams Category: Experimental IBM S. Kamat Lucent R. Guerin UPenn A. Orda Technion T. Przygienda Siara Systems August 1999

QoS Routing Mechanisms and OSPF Extensions

Status of this Memo

This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested. Distribution of this memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (1999). All Rights Reserved.

Abstract

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.

Apostolopoulos, et al. Experimental [Page 1]

RFC 2676 QoS Routing Mechanisms and OSPF Extensions August 1999

Table of Contents

1. Introduction 3 1.1. Overall Framework . . . . . . . . . . . . . . . . . . . . 3 1.2. Simplifying Assumptions . . . . . . . . . . . . . . . . . 5 2. Path Selection Information and Algorithms 7 2.1. Metrics . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.2. Advertisement of Link State Information . . . . . . . . . 8 2.3. Path Selection . . . . . . . . . . . . . . . . . . . . .10 2.3.1. Path Computation Algorithm . . . . . . . . . . .11 3. OSPF Protocol Extensions 16 3.1. QoS -- Optional Capabilities . . . . . . . . . . . . . .17 3.2. Encoding Resources as Extended TOS . . . . . . . . . . .17 3.2.1. Encoding bandwidth resource . . . . . . . . . . .19 3.2.2. Encoding Delay . . . . . . . . . . . . . . . . .21 3.3. Packet Formats . . . . . . . . . . . . . . . . . . . . .21 3.4. Calculating the Inter-area Routes . . . . . . . . . . . .22 3.5. Open Issues . . . . . . . . . . . . . . . . . . . . . . .22 4. A Reference Implementation based on GateD 22 4.1. The Gate Daemon (GateD) Program . . . . . . . . . . . . .22 4.2. Implementing the QoS Extensions of OSPF . . . . . . . . .23 4.2.1. Design Objectives and Scope . . . . . . . . . . .23 4.2.2. Architecture . . . . . . . . . . . . . . . . . .24 4.3. Major Implementation Issues . . . . . . . . . . . . . . .25 4.4. Bandwidth and Processing Overhead of QoS Routing . . . .29 5. Security Considerations 32 A. Pseudocode for the BF Based Pre-Computation Algorithm 33 B. On-Demand Dijkstra Algorithm for QoS Path Computation 36 C. Precomputation...

Processing...
Loading...