School of Education

Internet Technologies At Work

Chapter 11: Internet Architecture

After completing Chapter 11, you will know how to:

IETF

The Internet Engineering Task Force (IETF) is the standards body that is in charge of defining the Internet’s protocols. Any interested person or organization can join the IETF by following the link to membership at www.ietf.org.

RFC Process

The IETF defines the protocols through a Request for Comments (RFC) process. Most of the RFCs are generated by working committees of the IETF, but any individual or organization can submit an RFC for the IETF to consider. You can see any RFC by typing its number into the search engine at www.ietf.org/rfc.html. The IETF also maintains a complete list of all the RFCs in numerical (i.e., chronological) order. It is exciting to peruse this list and reflect on the continually evolving nature of the Internet.

End of Chapter Labs

Lab Project 11.1: Creating an Internet Address Allocation Plan

Imagine that a lot of turnover occurred in the IT division at your school or workplace, and there are shoddy records of which computers were assigned to different IP addresses. Your superior has asked you to review the situation and create a revised IP address allocation plan for your school or workplace. Use your word processor to write an essay in which you assess the current situation and present your plan for revamping the IP address allocation. In developing this plan, consider the following issues:

  1. Domain name space. Does your organization have a class A, B, or C Internet address space? Does this class have a sufficient number of addresses to cover the number of hosts that need external IP addresses?
  2. Private IP address range. What is the specified range of private IP addresses for your organization’s Internet address class?  If your organization has workstations that have private IP addresses, are these addresses within the specified range for your address class?
  3. Proxy servers. Consider whether your organization could use proxy servers to save costs and bolster security by hiding workstations on the internal network from hackers and crackers on the public Internet. If proxies are already in place make sure they are configured to assign IP addresses within the correct range.
  4. Static versus dynamic configuration. How many of the network hosts need to be statically configured? Could you save time and cost by letting the others use DHCP?
  5. Current IP Address Outline. Create an outline that lists the current names and IP addresses of each network host within your organization. Use indentations to group the hosts under the subdomain or subnet to which they belong. For workstations that obtain temporary IP addresses via dynamic configuration, write DHCP in place of the IP address. 
  6. Planned IP Address Outline. Create an outline that shows how you propose to revise the current IP addressing scheme. Depending on how closely this revision follows the current addressing scheme, you may be able to add a “proposed” column to the outline you created in the previous step; otherwise, you will need to create a separate outline of your planned IP addressing scheme.

If your instructor asked you to hand in the IP address allocation plan, make sure you put your name at the top of the essay, then copy it onto a disk or follow the other instructions you may have been given for submitting this assignment.

Lab Project 11.2: Preparing a Network Troubleshooting Guide

Networking problems can cause a lot of lost time and productivity when workers are unable to perform their jobs in a transaction oriented workplace. Imagine that out of concern over these kinds of delays, your employer has asked you to prepare a network troubleshooting guide. The purpose of this guide is twofold. First, it will consist of a section intended for end users to diagnose and report network problems that non-technical users cannot repair on their own. Second, the guide will contain a troubleshooting procedure for IT staff and more technically inclined users, who may be able to ease the burden on the IT staff by learning how to solve simple problems on their own. Use your word processor to write an essay in which you present your network troubleshooting guide. In formulating this guide, consider the following issues:

  1. Configuration problems. Many network failures, especially with newly acquired workstations, result from incorrect PC network configuration. Include instructions for checking the PC configuration to ensure that the IP address, subnet mask, DNS server address, and gateway settings are correct.
  2. Ping. The ping utility enables users to check for basic connectivity with other network devices. Include instructions for using ping to reach strategic network addresses, such as the nearest router and DNS server. If users can reach these devices, their network segment has connectivity.
  3. Problem Reporting. Provide users with a format for reporting problems they cannot solve on their own. Ask users to report whether the problem always happens or is intermittent. If it is intermittent, ask whether the user can make the problem recur, and if so, ask what the user does to make the problem happen. Ask whether the problem happens on just a single workstation or if other workstations have the same issue. If so, ask which specific workstations have the problem. Ask users to differentiate between total outages versus slow response times, and specify whether the slow periods are related to the time of day. Ask the user to describe any hardware or software changes that may have been made recently to the problematic workstation or local network segment.
  4. Equipment for Testing. To troubleshoot connectivity problems, you will need spare network cables with connectors of the type used on your network. Swapping a questionable cable with one you know works is an effective way to determine whether you have a failed cable. Similarly, swapping a hub with a spare that you know works is a good way to determine whether a local hub has failed. More sophisticated problems can be diagnosed by plugging in a laptop running network troubleshooting software that can identify specific problems on the local network segment.
  5. Other Troubleshooting Guides. There are several network troubleshooting guides on the Internet. Use Google or Yahoo to search for the keywords “network troubleshooting guide.” Perusing guidelines from the major networking vendors such as 3COM, Cabletron, and Cisco will give you ideas for techniques and strategies to include in your local troubleshooting guide.

If your instructor asked you to hand in the network troubleshooting guide, make sure you put your name at the top of the essay, then copy it onto a disk or follow the other instructions you may have been given for submitting this assignment.