CS457/557 - Computer Networks: Chapter 1 - the Current State of the Data Communications Industry

Objectives

1. Understand today's data communications industry as a system of interacting components
2. Understand the driving forces at work within the data communications industry
3. Understand the current state of the data communications industry as well as the major issues facing each of the industry's components
4. Understand the likely future scenarios for various data communications industry constituencies
5. Understand the structure and importance of the top-down model
6. Understand the relationship of network analysis and design to information systems analysis and design

Introduction

• What is Data Communications? - transmission of encoded data via electrical / optical means from one location to another

• The Best Way to Approach Data Communications (Goldman's Law of Data Communications)
  1. You will never know all there is to know about data communications.
  2. Be honest with yourself concerning what you don't know.
  3. There are no Data Communications police.
  4. If the network doesn't make good business sense, it probably makes no sense.
  5. Technical details are important,Technical details are important,Technical details are important.
  6. There is no such thing as a data communications failure, only networking solutions as yet unfound.
  7. Beware of self-proclaimed data communications experts.
  8. It is more important to be able to ask data communications questions than it is to be able to supply data communications answers.
  9. IF you're not moving forward, they you're losing ground to someone who is.

Data Communications as a System

• Regulators and Carriers
• Legislature and Judical Processes
• Standards-Making Agencies
• Manufacters and Vendors / Consultants
• Technology and Research
• Business

Regulators and Carriers

Divestiture and Deregulation

• pre-1980 - AT&T monopoly
• 1982 - Modified Final Judgement (MFJ) by Federal Judge Harold Greene
  resulted in AT&T and 7 Regional Bell Operating Companies
• 1991 - telecommunications companies can sell information services over their own networks

Politics and the Legislature and Judical Processes

• 1971 - MCI could compete with AT&T
• 1974 - involved Justice Dept. involvement
• 1982 - MFJ
• 1996 - Communications and Decency Act

Role of Standards-Making Agencies in Data Communications

1. Physical standards, RS232 interface = physical standard for the DB-25 connector
2. Operational Specifications, Token Ring Networks

How Does the Standards Making Process Work?

Standards Organizations:

• ISO (International Standards Organization) - OSI 7-layer model
• CCITT (Comite Consultatif International Telegraphique et Telephonique) - telecommunications standards
• ITU-T (International Telecommunications Union)
• ANSI (American National Standards Institute) - information systems standards
• IEEE (Institute of Electrical and Electronic Engineers) - local area network standards

OSI (Open Systems Interconnection) 7-Layer Model

1. : Applications - user interface layer
2. : Presentaton - data representation layer
3. : Session - enables two applications to communicate across a network
4. : Transport - assures reliable transmission
5. : Network - sets up pathways
6. : DataLink - puts messages together with headers
7. : Physical - transmits bits over the physical medium

Standards Making Process

1. Recognition of the need for a standard
2. Formation of a committee or task force
3. Information / Recommendation gathering
4. Tentative / alternative standards issued
5. Feedback on tentative standards
6. Final standards issued
7. Compliance with final standards

What do Manufacters have to Gain/Lose from Standards?

• Development Precedes Standardization (HTML 3.0)
• Economic Power of Standards (MS-DOS vs. CPM

What should users be aware of regarding standards?

• Standards Extensions - Netscape and MS extensions
• Jargon Jungle - bridge, router, brouter, bridging router

Data Communcatons is Business

Technology as an Enabler

1. getting bits of data delivered faster
2. getting bits of data delivered cheaper

The I-P-O Model

1. Input
2. Process
3. Output

Business Demand + Available Technology = Emerging Network Services

1. network companies are in business to make a profit
2. network companies need to sell the network services which business is willing to buy at a price business is willing to pay

Top-Down Approach

Top-Down Model

Technology Investment versus Worker Productivity

Job Opportunities for the Data Communications Professional

• Business
• Technology
• Carriers

Critical Skills for Data Communications Professionals

1. Understand and can speak "business"
2. Understand and can evaluate technology with a critical eye as to the cost/benefit of that technology
3. Understand comparative value and proper application of available network services and can work effectively with carriers to see that implementations are completed properly and cost effectively
4. Can communicate effectively with technically oriented people as well as with business management personnel

Slides

Review Questions: [e-mail your answers (where possible) to summers_wayne@ColumbusState.edu before 4 p.m. on Tues., Sept. 1, 1998]

Activities: