ISDN vs. Cable modems

Essay by Robert CorrierUniversity, Bachelor'sA+, August 1996

download word file, 11 pages 4.7

1.0 Introduction

The Internet is a network of networks that interconnects computers around

the world, supporting both business and residential users. In 1994, a

multimedia Internet application known as the World Wide Web became

popular. The higher bandwidth needs of this application have highlighted

the limited Internet access speeds available to residential users. Even at 28.8

Kilobits per second (Kbps)--the fastest residential access commonly

available at the time of this writing--the transfer of graphical images can be

frustratingly slow.

This report examines two enhancements to existing residential

communications infrastructure: Integrated Services Digital Network (ISDN),

and cable television networks upgraded to pass bi-directional digital traffic

(Cable Modems). It analyzes the potential of each enhancement to deliver

Internet access to residential users. It validates the hypothesis that upgraded

cable networks can deliver residential Internet access more cost-effectively,

while offering a broader range of services.

The research for this report consisted of case studies of two commercial

deployments of residential Internet access, each introduced in the spring of


· Continental Cablevision and Performance Systems International (PSI)

jointly developed PSICable, an Internet access service deployed over

upgraded cable plant in Cambridge, Massachusetts;

· Internex, Inc.

began selling Internet access over ISDN telephone

circuits available from Pacific Bell. Internex's customers are residences and

small businesses in the 'Silicon Valley' area south of San Francisco,


2.0 The Internet

When a home is connected to the Internet, residential communications

infrastructure serves as the 'last mile' of the connection between the

home computer and the rest of the computers on the Internet. This

section describes the Internet technology involved in that connection.

This section does not discuss other aspects of Internet technology in

detail; that is well done elsewhere. Rather, it focuses on the services

that need to be provided for home computer users to...