Alcatel-Lucent Scalable IP Networks Self-Study Guide

Preparing for the Network Routing Specialist I (NRS 1) Certification Exam

Kent Hundley

• Publisher: Wiley
• Year: 2018
• Print ISBN: 9780470429068
• eBook ISBN: 9781119523420
• Edition: 1
• Topic: Computer Science
• Subtopic: Computer Networking
• Index: Computer Science

By offering the new Service Routing Certification Program, Alcatel-Lucent is extending their reach and knowledge to networking professionals with a comprehensive demonstration of how to build smart, scalable networks. Serving as a course in a book from Alcatel-Lucentthe world leader in designing and developing scalable systemsthis resource pinpoints the pitfalls to avoid when building scalable networks, examines the most successful techniques available for engineers who are building and operating IP networks, and provides overviews of the Internet, IP routing and the IP layer, and the practice of opening the shortest path first.

1
Introduction To Networking

The Alcatel-Lucent NRS I exam topics covered in this chapter include the following:

• The significance of the ARPANET
• The problems with having different protocols, and the solutions
• How the Internet evolved from a military-based network to a research-based network and then into a commercial network
• An overview of the modern Internet
• Differences between an Internet provider and a content provider
• Differences between traditional and modern ISP services
• The advantages of protocol layering
• The characteristics of the TCP/IP protocol layers, and how the layers work together
• The definition and development of the OSI Reference Model
• The similarities between the TCI/IP and OSI models of protocol

This chapter provides an introduction to the history and principles that underlie the Internet, the biggest network in the world. It is important that you have a foundational understanding of the hardware and software components that constitue the Internet in order to fully appreciate the remaining topics in the chapters that follow. The Internet has gone through large evolutionary changes in its lifetime, and these changes provide key insights into modern networking principles and design philosophies. We also discuss the development of the TCP/IP protocol, protocol layering, and the relationship of the OSI model to modern networking.

Pre-Assessment

The following assessment questions will help you understand what areas of the chapter you should review in more detail to prepare for the exam.

1. 1. The original network that ultimately became the Internet was called
   1. A. NSFNET
   2. B. ARPANET
   3. C. DoDnet
   4. D. DARPA
2. 2. The primary organization behind the development of the original Internet was
   1. A. IBM
   2. B. Digital Equipment Corporation (DEC)
   3. C. Stanford University
   4. D. the U.S. Department of Defense
3. 3. Which of the following was not a primary design concern during the development of the original Internet?
   1. A. Reliability
   2. B. Bandwidth
   3. C. Interoperability
   4. D. Support for diverse network mediums
4. 4. Which of the following was not a reason TCP was a superior transport protocol to NCP?
   1. A. Support for global addressing
   2. B. Support for end-to-end checksums
   3. C. Support for applications such as email
   4. D. Support for fragmentation and reassembly
5. 5. Which of the following OSI layers is not paired with the correct implementation?
   1. A. Layer 7—Email
   2. B. Layer 3—TCP
   3. C. Layer 4—UDP
   4. D. Layer 2—PPP

You will find the answers to each of these questions in Appendix A. You can also download all of the CD materials for this book at http://booksupport.wiley.com to take all the assessment tests and review the answers.

1.1: Before the Internet

In the earliest days of computing circa the late 1960s, the majority of companies purchased only a single large system to handle all of their data processing needs. The systems were proprietary and closed, using hardware and software architectures that were compatible only with the same manufacturers’s equipment. The basic components were large central mainframes that connected to intelligent communications “controllers,” into which were plugged “dumb” terminals and printers. Network communication consisted entirely of the data sent between a terminal or printer and the mainframe. The terminals were incapable of local storage or configuration, and all intelligence in the entire system resided on the mainframe.

If companies wanted to expand their operations, they were locked into single vendors such as IBM or Digital Equipment Corporation. This led to serious compatibility issues when different organizations within a company or different companies needed to communicate with each other because cross-platform communication did not exist. There was no easy solution to this problem, and the dominant vendors had no incentive to ensure that their systems were compatible with those of other manufacturers.

The U.S. military found itself in an untenable situation when it realized that its different computer systems around the country could not communicate with each other because of proprietary systems and protocols. This meant that different sites could not share data or resources, and in the event of a disaster or systems failure, large amounts of information would be unavailable. It was this realization of the need for systems that could share information and back each other up that drove the creation of the original “Internet.” In those early days, it was known as the ARPANET.

ARPANET: Genesis of the Internet

The ARPANET was conceived by the Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense (DoD) to be the first cross-organizational communications network. It became the world’s first packet-switched network, eventually leading to today’s modern Internet. Its beginnings were humble, consisting of only four sites at Stanford, UC Santa Barbara, UCLA, and the University of Utah.

Owing to its military origins, in addition to information-sharing capabilities, the ARPANET was also designed with redundancy in mind. This was the Cold War era, and any communications system had to be able to survive a Soviet nuclear strike on any single or even multiple locations without complete failure. With this in mind, the system was designed with redundant packet switches, links, and a protocol to move data that could dynamically route around failed links and locations. Figure 1.1 shows an early drawing of the proposed network.

Connecting physical components and physical links was merely the first step in the development of the ARPANET, however. In order to make the system truly useful, it would have to support the ability for disparate devices to communicate with each other in a reliable fashion. These systems might be from a variety of manufacturers, and they might be connected to networks in various ways such as by radio or satellite.

As an example, in 1969 the Advanced Research Projects Agency (ARPA) had funded an experimental packet radio network under the direction of Professor Norman Abramson at the University of Hawaii called, appropriately enough, ALOHANET. The network connected sites spread around the Hawaiian Islands to a central time-sharing computer on the University of Hawaii campus. ALOHANET users could connect to the ARPANET, but the ALOHANET was not part of the ARPANET core, so from ARPANET’s perspective, it was just a terminal connection.

Figure 1.1 The original ARPA network had only four nodes.

Other developments began to transpire to drive the ARPANET’s need for heterogeneous communications. Robert Kahn, a Bolt, Baranek, and Newman researcher who had been instrumental in designing the ARPANET and improving its reliability, had been organizing an event to demonstrate the ARPANET. During this event in the spring of 1973, a new working group called the International Network Working Group (INWG) was organized.

One of the tasks that the INWG decided to undertake was to connect ARPANET and ALOHANET to some of the new packet-switching European networks to create a giant global network. Robert Kahn began a lengthy series of discussions with Vint Cerf, the INWG chairman, to find a solution to their mutual challenges.

Their model was an internetworking of ARPANET with ALOHANET and a satellite network (SATNET)—each of which used different communication protocols and different physical int...

Table of contents

• Cover
• Table of Contents
• About the Author
• Foreword
• Introduction
• 1 Introduction To Networking
• 2 The Alcatel-Lucent 7750 SR and 7450 ESS Components and the Command-Line Interface
• 3 Data Link Overview
• 4 Switched Networks, Spanning Tree, and VLANs
• 5 IP Addressing
• 6 IP Forwarding and Services
• 7 Transport Layer Services—TCP and UDP
• 8 Introduction to IP Routing
• 9 OSPF
• 10 BGP
• 11 MPLS and VPN Services
• A: Chapter Assessment Questions and Answers
• B: Lab Exercises and Solutions
• Glossary
• Index
• Wiley Publishing, Inc. End-User License Agreement
• Service Routing Must Reads from Alcatel-Lucent
• End User License Agreement