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  • Topic: Asynchronous Transfer Mode, Data transmission, Error detection and correction
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  • Published : March 15, 2013
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Traffic Management in ATM Networks Over Satellite Links

Rohit Goyal, Raj Jain, Mukul Goyal, Sonia Fahmy, Bobby Vandalore Department of Computer Information Science
2015 Neil Ave, DL395
Columbus, OH 43210
Phone: (614)-688-4482. Fax: (614)-292-2911.
Email: goyal@cis.ohio-state.edu, jain@cis.ohio-state.edu

Tom vonDeak
NASA Lewis Research Center
21000 Brookpark Road, MS 54-2
Cleveland, OH 44135
Phone: 216-433-3277 Fax: 216-433-8705
Email: tvondeak@lerc.nasa.gov

Abstract

This report presents a survey of the traffic management issues in the designing and implementation of satellite-ATM networks. First a reference satellite-ATM network architecture is presented along with an overview of the service categories available in ATM networks. The error characteristics of satellite channels, and techniques to improve the error characteristics, and the impact on ATM network performance are then discussed. A delay model for satellite networks and the major components of delay and delay variation are described. A survey of design options for TCP over UBR, GFR and ABR services in ATM is presented next. The main focuses is on traffic management issues. Several recommendations on the design options for efficiently carrying data services over satellite-ATM networks are presented.

Table of Contents

1 Introduction3
2 Architectural Issues4
2.1 A Reference Architecture for Satellite-ATM Networks5
2.2 Service Categories in ATM Networks7
3 Satellite Channel Error Characteristics98
3.1 Impact of bursty errors on the ATM layer10
3.2 Impact of bursty errors on AAL protocols12
3.3 Impact of Bursty Errors on Physical Layer Protocols13
3.4 Solutions for Improving Error Characteristics17
3.5 Performance Studies of Reed-Solomon codes18
3.6 COMSAT's ATM Link Enhancement (ALE) technique19
4 Satellite Delay Characteristics21
4.1 Delay Requirements of Applications2221
4.2 Satellite Network Delay Model2322
4.3 Delay Variation Characteristics25
5 Media Access Protocols for ATM over Satellite2726
6 TCP Over Satellite-ATM: Interoperability Issues2726
6.1 TCP congestion control28
6.2 Design Issues for TCP/IP over ATM30
7 UBR and UBR+33
7.1 Performance Metrics34
7.2 TCP over UBR: Performance35
7.3 UBR+: Enhancements to UBR36
7.4 TCP Enhancements42
7.5 Buffer Requirements for TCP over UBR+43
7.6 Guaranteed Frame Rate49
8 ABR over Satellite53
8.1 ABR Service Overview53
8.2 ABR Source Rules54
8.2.1 ABR Source Rule 5 over Satellite54
8.2.2 ABR Source Rule 6 on ABR over Satellite55
8.3 ABR Switch Schemes59
8.4 TCP over ABR60
8.4.1 Nature of TCP Traffic at the ATM Layer60
8.4.2 TCP Performance over ABR61
8.4.3 Buffer Requirements for TCP over ABR63
8.4.4 TCP over ABR: Switch Design Issues66
8.4.5 TCP Performance over Backbone ATM-ABR Networks67
8.5 Virtual Source / Virtual Destination69
9 References71

1. Introduction

ATM technology is expected to provide quality of service based networks that support voice, video and data applications. ATM was originally designed for fiber based terrestrial networks that exhibit low latencies and low error rates. With the widespread availability of multimedia technology, and an increasing demand for electronic connectivity across the world, satellite networks will play an indispensable role in the deployment of global networks. Ka-band satellites using the gigahertz frequency spectrum can reach user terminals across most of the populated world. As a result, ATM based satellite networks can be effectively used to provide real time as well as non-real time communications services to remote areas.

Satellite communications technology offers a number of advantages over traditional terrestrial point-to-point networks [AKYL97]. These include,

• wide geographic coverage including interconnection of “ATM islands”,

• multipoint to multipoint communications facilitated by the inherent...
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