CH-1-4 Introduction to Networking – Network+ Guide to Networks : Chapter Notes

This Document Contains Chapters 1 to 4 Chapter 1 Introduction to Networking At a Glance Instructor’s Manual Table of Contents • Overview • Objectives • Teaching Tips • Quick Quizzes • Class Discussion Topics • Additional Projects • Additional Resources • Key Terms Lecture Notes Overview Loosely defined, a network is a group of computers and other devices connected by some type of transmission media. Variations on the elements of a network and its design, however, are nearly infinite. A network can be as small as two computers connected by a cable in a home office or the largest network all, the Internet, made up of billions of computers and other devices connected across the world via a combination of cable, phone lines, and wireless links. Networks might link cell phones, personal computers, mainframe computers, printers, corporate phone systems, security cameras, vehicles, and wearable technology devices. They might communicate through copper wires, fiber-optic cable, or radio waves. This chapter introduces students to the fundamentals of networks and how technicians support them. Chapter Objectives After reading this chapter and completing the exercises, the student will be able to: • Distinguish between client-server and peer-to-peer models used to control access to a network • Identify types of applications and protocols used on a network • Describe various networking hardware devices and the most common physical topologies • Describe the seven layers of the OSI model • Explore best practices for safety when working with networks and computers • Describe the seven-step troubleshooting model for solving a networking problem Teaching Tips Network Models 1. Define and describe the term topology. Discuss the two types of topology students will need to understand: • physical topology • logical topology 2. Explain that controlling how users and programs get access to the resources on a network is a function of the OS used on the network. 3. Introduce students to the peer-to-peer and the client-server network models. Point out that the client-server model requires one or more network operating systems (NOS). Peer-to-Peer Model 1. Discuss the characteristics of a P2P (peer-to-peer) network model. 2. Describe the characteristics of a traditional peer-to-peer network. 3. Use Figure 1-1 to illustrate resource sharing on a peer-to-peer network. 4. Discuss the three ways resources can be shared if all computers in a P2P network are running a Windows OS. 5. Describe the advantages of peer-to-peer networks. 6. Describe the disadvantages of peer-to-peer networks. Teaching Tip Be sure to emphasize that modifying file-sharing controls is operating system dependent and that this method of resource sharing may lead to access controls that are not uniform or secure. Client-Server Network Model 1. Introduce the client/server model. Use Figure 1-2 in your discussion. 2. Define and describe a Windows domain. Point out the centralized database that contains user account information and security for the entire group of computers is called Active Directory (AD). 3. Point out that a Microsoft account links local domain resources with Microsoft cloud resources. Compare this type of account to a local account, which is specific to a domain. Teaching Tip Students can learn more about Microsoft Active Directory by visiting: https://docs.microsoft.com/en-us/windows-server/identity/ad-ds/get-started/virtual-dc/active-directory-domain-services-overview 4. Describe how clients and servers communicate. 5. Provide examples of current Network Operating Systems and discuss some of the tasks that a NOS is responsible. 6. Describe the disadvantage of a client/server network relative to a peer-to-peer network. 7. Describe the advantages of a client/server network relative to a peer-to-peer network. Client-Server Applications 1. Define network services. 2. Explain that a client-server application involves two computers: • client computer • server 3. Use Figure 1-3 to demonstrate how a client and server communicate across a network. 4. Define and discuss protocols. Teaching Tip Be sure to emphasize that it is possible for a computer to act as both a client and a server and explain how this might occur. 5. Discuss several popular client-server applications used on networks and the Internet: • web service • email services • FTP service • Telnet service • remote applications • Remote Desktop Network Hardware 1. Introduce this section by using Figure 1-6 to discuss networking hardware and how that hardware is connected together. LANs and Their Hardware 1. Define and describe a LAN. Mention that LANs are usually contained in a small space, such as an office or building. 2. Define and describe a switch. 3. Introduce the star topology. Use Figure 1-6 to illustrate a typical star topology network. 4. Compare a star topology to a mesh topology, where each device connects to multiple other devices. Use Figure 1-1 to illustrate a mesh topology. 5. Use Figure 1-8 to discuss the concept of a network port. 6. Define and describe NICs (network interface cards). Use Figure 1-9 in your discussion. Point out that a NIC may also be called a network adapter. 7. Introduce the concept of a network backbone. 8. Note the cabling needs for a network backbone and discuss why they are important. 9. Introduce the bus topology as devices that are daisy-chained together. 10. Define and describe the star-bus topology, which is a type of hybrid topology. Use Figure 1-10 to illustrate a star-bus topology. 11. Define and describe a router as a device that manages traffic between two or more networks. Mention that a very important function of a router is to determine the best path for traffic to go through in order to reach its destination. 12. Use Figures 1-12 and 1-13 to discuss the difference between a switch and a router. MANs and WANs 1. Define and describe a WAN as a group of LANs that spread over a wide 2. Define and describe a MAN. Point out that a MAN may also be called a CAN. 3. Use Figure 1-14 to illustrate a WAN connecting two LANs in different geographical areas. Teaching Tip Be sure to mention that the Internet the largest and most varied WAN in the world. Quick Quiz 1 1. Which of the following protocols is used by a client to send an email message? a. HTTP b. SMTP c. FTP d. RDP Answer: B 2. When Windows Server controls network access to a group of computers, this logical group is called which of the following? a. workgroup b. homegroup c. domain d. access group Answer: C 3. True or False: A client/server network is the simplest network model. Answer: False 4. A _____ is a central conduit that connects the segments (pieces) of a network. Answer: backbone 5. A network that is larger than a LAN and connects clients and servers from multiple buildings is known as which of the following? a. WAN b. MAN c. PAN d. LAN Answer: b The Seven-Layer OSI Model 1. Use Figure 1-15 to compare network communications and the US Postal Service. 2. Define and describe the OSI reference model. Stress the importance of using the OSI model to help understand networking protocols and to troubleshoot network problems. 3. Introduce the seven layers of the OSI model. Use Figure 1-16 in your discussion. 4. Emphasize that the OSI model is a theoretical representation of what happens between two nodes communicating on a network. Teaching Tip Students may find more information on the OSI Model's seven layers at http://support.microsoft.com/kb/103884 Layer 7: Application Layer 1. Introduce and describe the Application layer. 2. Explain how the Application Layer facilitates communication between software applications and lower-layer network services. 3. Point out that data passed between applications or utility programs and the OS is called a payload. Layer 6: Presentation Layer 1. Introduce and describe the Presentation layer as being responsible for reformatting, compressing, and/or encrypting data in a way that the application on the receiving end can read. 2. Explain how the Presentation layer services also manage data encryption (such as the scrambling of passwords) and decryption. Layer 5: Session Layer 1. Introduce and describe the function of the Session layer. 2. Explain how the term session is used to describe an established connection between two end points. 3. Point out that most tasks are performed by the OS when an application makes an API call to the OS. Layer 4: Transport Layer 1. Introduce and describe the function of the Transport layer. 2. Define and describe TCP and the characteristics of a connection-oriented protocol. 3. Define and describe UDP and the characteristics of a connectionless protocol. 4. Define encapsulation as the process of adding of a header to the data inherited from the layer above. 5. Discuss the Transport layer’s use of ports numbers. 6. Point out that TCP messages are divided into smaller messages called segments and UDP messages are known as a datagram. Layer 3: Network Layer 1. Introduce and describe the function of the Network layer. 2. Note that the IP protocol is the most common Network layer protocol. 3. Explain how the data unit accepted from the Transport layer is transformed into a packet. • 4. Define and discuss an IP address. Mention that because an IP address is used by the Network layer, it may also be known as a network address. 5. Point out that IP relies on several routing protocols to find the best route for a packet when traversing several networks on its way to its destination. • 6. Define and discuss fragmentation, which is a process that divides a packet into smaller packets. Layer 2: Data Link Layer 1. Introduce and describe the function of the Data Link layer. 2. Point out that switches and NICs operate at this layer. 3. Explain that the Data Link layer puts its own control information in a header and attaches control information to the end of the packet (called a trailer) that was received from the Network layer above. The entire Data Link layer message is then called a frame. 4. Describe the communication mishap referred to as partial communication. 5. Describe a MAC address as a Layer 2 address that is found on every network adapter on the globe. Mention that a MAC address may also be referred to as a physical address, hardware address, or a Data Link layer address. Layer 1: Physical Layer 1. Introduce and describe the function of the Physical layer. 2. Explain the different signal types corresponding to the different transmission media. Protocol Data Unit or PDU 1. Describe a PDU (protocol data units) and explain how it flows through the model. 2. Use Table 1-1 to discuss the different names for a PDU as it moves from one layer to another. Summary of How the Layers Work Together 1. Use Figure 1-17 and Table 1-2 to describe the steps through the OSI layers during a browser-to-Web server transmission. Safety Procedures and Policies Emergency Procedures 1. Discuss the importance of knowing the best escape route in the event of an emergency. 2. Describe the components of a fire suppression system: a. emergency alert system b. portable fire extinguishers c. emergency power-off switch d. suppression agent 3. Discuss the difference between a fail open and a fail close. Point out that a fail-open policy is often based on common sense so as to ensure that, in an emergency, no one is harmed when a system is not working. 4. Explain that a material safety data sheet (MSDS) explains how to properly handle substances such as chemical solvents and how to dispose of them. Safety Precautions 1. Explain that electrical and tool safety in workplaces is generally regulated by OSHA. 2. Discuss the general OSHA guidelines that should be followed when using power tools or other hand tools in the workplace: a. Wear PPE (personal protective equipment) b. Keep all tools in good condition and properly stored c. Use the right tool for the job d. Watch out for trip hazards 3. Describe the guidelines that should be followed when lifting heavy objects. 4. Define and describe grounding. 5. Discuss the negative effects that static electricity (ESD) can have on electronic components. 6. Describe the steps that should be followed before touching a component. Troubleshooting Network Problems 1. Introduce basic troubleshooting methodology. 2. Use Figure 1-21 to describe each of the seven steps of the troubleshooting methodology. 3. Demonstrate using the seven steps to troubleshoot a failed network connection (see “Applying Concepts: Troubleshoot a Failed Network Connection”). Quick Quiz 2 1. What is the seventh layer of the OSI model? a. Physical layer b. Transport layer c. Application layer d. Session layer Answer: C 2. The name given to a group of bits as it moves from one layer of the OSI model to the next is which of the following? a. frame b. packet c. segment d. protocol data unit (PDU) Answer: D 3. Protocols in the ____ layer accept data from the Session layer and manage end-to-end delivery of data. Answer: Transport 4. True or False: The IP (Internet Protocol) operates in the Transport layer. Answer: False 5. The least intelligent switches operate at which layer of the OSI model? a. Physical layer b. Transport layer c. Session layer d. Data Link layer Answer: D Class Discussion Topics 1. Discuss the differences and similarities between a peer-to peer network and a client server network. 2. As a class, discuss the difference between a physical topology and a logical topology. Why are both necessary? Additional Projects 1. The student has learned that the OSI model allows TCP to function at the Transport layer and IP to function at the Network layer. Have the students’ research TCP/IP protocols in more depth in relation to the OSI model. The students should then prepare a report summarizing their research. Included in the report should be a critique of the question, “Does the OSI models conform to TCP/IP protocols, or vice versa? Require students to defend their thoughts. Additional Resources 1. Understanding Client-Server Applications https://www.experts-exchange.com/articles/11271/Understanding-Client-Server-Protocols-and-Web-Applications.html 2. Client-Server vs. Peer Networks http://www.tomshardware.com/reviews/local-area-network-wi-fi-wireless,3020-2.html 3. The Seven Layers of the OSI Model http://www.webopedia.com/quick_ref/OSI_Layers.asp 4. How Stuff Works – Networking Library http://computer.howstuffworks.com/computer-networking-channel.htm Key Terms For definitions of key terms, see the Glossary near the end of the book.  Active Directory (AD)  Active Directory Domain Services (AD DS)  API (application programming interface) call  Application layer  backbone  bus topology  CAN (campus area network)  catastrophic failure  client  client-server applications  client-server network model  connectionless protocol  connection-oriented protocol  Data Link layer  Data Link layer address  datagram  decapsulation  domain  emergency alert system  encapsulation  ESD (electrostatic discharge)  fail close  fail open  fire suppression system  firmware  fragmentation  frame  FTP (File Transfer Protocol)  grounding  hardware address  header  host  HTTP (Hypertext Transfer Protocol)  HTTPS (HTTP Secure)  hub  hybrid topology  IMAP4 (Internet Message Access Protocol, version 4)  IP (Internet Protocol)  IP address  knowledge base  local area network (LAN)  logical topology  MAC (Media Access Control) address  MAN (metropolitan area network)  mesh topology  material safety data sheet (MSDS)  network  network interface card (NIC)  Network layer  network operating system (NOS)  network services  node  OSHA (Occupational Safety and Health Administration)  OSI (Open Systems Interconnection) reference model  peer-to-peer (P2P) network  Packet  PAN (personal area network)  payload  protocol data unit (PDU)  physical address  Physical layer  physical topology  POP3 (Post Office Protocol, version 3)  port number  PPE (personal protective equipment)  Presentation layer  protocol  RDP (Remote Desktop Protocol)  remote application  Remote Desktop Services  ring topology  router  scalable  segment  server  Session layer  SFTP (Secure File Transfer Protocol)  SMTP (Simple Mail Transfer Protocol)  SNMP (Simple Network Management Protocol)  SOHO (small office-home office)  SSH (Secure Shell)  SSL (Secure Sockets Layer)  star topology  star-bus topology  static electricity  switch  TCP (Transmission Control Protocol)  TCP/IP  Telnet  TLS (Transport Layer Security)  topology  trailer  Transport layer  trip hazard  UDP (User Datagram Protocol)  upset failure  WAN (wide area network) Chapter 2 Network Infrastructure and Documentation At a Glance Instructor’s Manual Table of Contents • Overview • Objectives • Teaching Tips • Quick Quizzes • Class Discussion Topics • Additional Projects • Additional Resources • Key Terms Lecture Notes Overview This chapter details the structural hardware necessary to connect and support these hosts, routers, and switches and connect them to the outside world. Students will learn about cabling, racks, equipment that monitors the environment, and other equipment that supports the physical network in a building or on a campus. They will also learn how critical it is to maintain good network documentation, so you can keep track of the complexities of a typical modern network. Finally, they’ll learn how to implement clear policies for managing changes to a network. Chapter Objectives After reading this chapter and completing the exercises, the student will be able to: • Identify and describe network and cabling equipment in commercial buildings and work areas • Create and analyze network diagrams • Explain operating procedures, inventory management, labeling conventions, and business documents for a typical network • Track the progress of changes made to a network Teaching Tips Components of Structured Cabling 1. Describe the TIA/EIA-568 Commercial Building Wiring Standard, also known as structured cabling. Explain that structured cabling is based on a hierarchical design and assumes a network is based on the star topology. From the Demarc to a Workstation 1. Use Figure 2-1 to illustrate the different components of structured cabling in an enterprise network. 2. Use Figure 2-2 to illustrate how structured cabling appears within a building. 3. The next section of the text outlines a tour of the physical network illustrated in Figure 2-1. Point out that a network begins at the demarcation point in the entrance facility. The tour covers three stops: a. Entrance facility in Building A b. Data room in Building B c. Work areas in all three buildings 4. Review the components of the tour outlined in the text: a. Entrance facility b. demark (demarcation point) c. MDF (main distribution frame/facility) d. data room e. racks f. patch panel g. VoIP telephone equipment h. IDF (intermediate distribution frame) i. Work area j. wall jacks 5. Use Figures 2-11 and 2-12 to discuss racks used for attaching devices such as routers, servers, switches, patch panels, audiovisual equipment, or telephony equipment. 6. Explain to students that rack system provide mounting hardware for network equipment to optimize the use of square footage in equipment rooms and ensure adequate spacing, access, and ventilation for these devices. 7. Mention that racks may be wall- or ceiling-mounted, or freestanding on the floor. 8. Explain that racks are measured in rack units (RU or U), with the standard being 42U tall (6 feet). 9. Point out that hardware should be installed as close to the front of the rack as possible to allow for proper airflow in the back. 10. Use Figure 2-14 to discuss hot aisle/cold aisle rack layout. 11. Discuss the three basic types of cable installations allowed by structured cabling standards: a. patch cable b. horizontal cabling c. backbone cabling 12. Use Figure 2-15 to illustrate a horizontal wiring configuration. 13. Use Figure 2-16 to illustrate a cable installation using UTP from the data room to the work area. 14. Discuss the various cable installation tips that will help prevent Physical layer failures: a. termination b. bend radius c. verify continuity d. cinch cables loosely e. protect cables f. avoid EMI g. plenum cabling h. grounding i. slack in cable runs j. cable trays k. patch panels l. company standards and stock m. documentation Teaching Tip Emphasize the vast knowledge required when specializing in cable installation, design, or maintenance, and the importance of investing in a reference dedicated to this topic. Teaching Tip Students may find more information on Cable Considerations for Network Installations at http://www.cablinginstall.com/articles/print/volume-6/issue-9/contents/design/network-design-and-installation-considerations.html Monitoring the Environment and Security 1. Explain that due to the sensitive nature of the equipment mounted on racks, environmental and security monitoring are critical preventative measures. 2. Point out that data rooms are often serviced by HVAC systems that are separate from the rest of the building. 3. Explain that specialized products are available that monitor the critical factors of a data closet’s environment. Quick Quiz 1 1. Which of the following terms best describe the first point of interconnection between an organization’s LAN or WAN and a service provider’s facility? a. data room b. MDF c. IDF d. work area Answer: B 2. The area above the ceiling tile or below the subflooring is known as which of the following? a. crosstalk b. cable trays c. plenum d. grounding Answer: C 3. True or False: A VoIP gateway device converts signals from a campus’s analog phone equipment into IP data that can travel over the Internet. Answer: True 4. How wide is a standard data equipment rack? a. 42” b. 12” c. 23” d. 19” Answer: D 5. Which of the following terms best describe the cables or wireless links that provide interconnection between the entrance facility and MDF? a. backbone b. patch c. demarc d. horizontal Answer: A Network Documentation Network Diagrams 1. Define and describe network diagrams. Point out that these diagrams may show physical layout, logical topology, IP address reserves, names of major network devices, and types of transmission media. Use Figures 2-21 and 2-22 in your discussion. 2. Explain that a network diagram can be created as a product of network mapping, which is the process of discovering and identifying the devices on a network. 3. Introduce students to Nmap, which is a simple and popular tools used to detect, identify, and monitor devices on your network. Point out that the GUI version is called Zenmap. 4. Use Figure 2-25 to illustrate a network diagram using Cisco symbols. 5. Direct students to Table 2-1, which shows several of the most common network topology icons. Point out that students can download a copy of all these symbols from Cisco’s website at cisco.com/c/en/us/about/brand-center/network-topology-icons.html 6. Define and describe a wiring schematic. 7. Use Figure 2-29 to illustrate a wiring schematic. 8. Explain that another diagram that students may come across is a rack diagram, which show the devices stacked in a rack system. Point out that these diagrams are typically drawn to scale. Use Figure 2-30 in your discussion. Operating Procedures 1. Explain that essential documentation covers: a. logical and physical connections on a network b. inventory management c. IP address utilization d. vendors e. internal operating procedures, policies, and standards 2. Use Table 2-2 to describe items to consider covering in network documentation. Point out that as information is compiled, it should be organized into a database that can be easily updated and searched. Inventory Management 1. Define system life cycle as the process of designing, implementing, and maintaining an entire network. Point out that a major part of this process is the removal and disposal of outdated assets and the addition of compatible, updated devices. 2. Explain that inventory management refers to the monitoring and maintaining of all the assets that make up a network. 3. Point out that the first step in inventory management is to list all the components on the network, which include: a. hardware – configuration files, model number, serial number, location on the network, and technical support contact b. software – version number, vendor, licensing, and technical support contact 4. Mention that inventory documentation provides network administrators with information about the costs and benefits of certain types of hardware or software. Labeling and Naming Conventions 1. Discuss the importance of establishing a naming convention when labeling devices. Further discuss the importance of labeling those devices with those names. 2. Discuss the naming convention tips outlined in the text: a. Use names that are as descriptive as possible b. Only include fields that are absolutely essential in identifying the device c. Don’t overcomplicate the name with useless or redundant information d. Pay attention to any established naming convention already in use by the employer e. Think big-picture-down-to-details when designing device name fields f. Consider any security risks from the details you might include in your naming convention 3. Discuss these tips for labeling: a. Use color-coded cables for different general purposes b. Label ports and jacks that cables connect to c. Where labels won’t fit on devices, draw a simple diagram of the device that indicates the purpose of each port, slot, and connector (see Figure 2-32) d. Use a portable label maker Business Documents 1. Explain to students that there are certain business documents that network professionals should be familiar with. Discuss the purpose and structure of the following: a. RFP (request for proposal) b. MOU (memorandum of understanding) c. SOW (statement of work) d. SLA (service-level agreement) e. MSA (master service agreement) f. MLA (master license agreement) Change Management 1. Explain why managing change while maintaining a network’s efficiency and availability requires good planning. 2. Introduce change management and techniques for approaching the most common types of software and hardware changes, from installing patches to replacing a network backbone. Software and Hardware Changes 1. Point out that an important part of keeping a system running optimally is upgrading its software. 2. Describe the four common software change types: a. patch b. upgrade c. rollback d. installation 3. Review the general steps involved in implementing software changes on a network. 4. Emphasize that generally, upgrading or patching software according to a vendor’s recommendations is a good idea and can often prevent network problems. 5. Explain that most technicians will encounter a situation when you must roll back changes. 6. Use Table 2-3 to summarize some basic options to reverse a software upgrade. 7. Discuss the change management principles that apply to any type of change: a. Process all changes through the proper channels b. Minimize negative impacts on business processes c. Plan thoroughly to maximize the chances of a successful change on the first attempt d. Document each change throughout the process Change Management Documentation 1. Point out that generally, the larger an organization, the more documentation is required when making hardware and software changes. 2. Explain that required processes and how these processes are documented are designed to protect the person making the change, users, managers, and the organization so that changes do not disrupt normal work flow. 3. Discuss the list of what to expect when managing hardware or software changes: a. Submit a change request document b. Understand and follow the approval process c. The change is project-managed d. Provide additional documentation e. Close the change Quick Quiz 2 1. Which of the following terms best describe the process of discovering and identifying the devices on a network? a. network diagram b. wiring scheme c. network mapping d. network graphing Answer: C 2. A graphical representation of a network’s wired infrastructure is known as a _________. Answer: wiring schematic 3. True or False: The first step in inventory management is to determine the cost and benefits of certain types of hardware and software. Answer: False 4. What type of document outlines the intentions of two or more parties to enter into a binding agreement, or contract, and is sometimes used between an informal handshake and the legally binding signatures on contracts? a. RFP (request for proposal) b. MOU (memorandum of understanding) c. SOW (statement of work) d. SLA (service-level agreement) Answer: B 5. Which of the following terms best describe a major change to a software package that enhances the functionality and features of the software, while also correcting bugs and vulnerabilities? a. service pack b. rollback c. back level d. upgrade Answer: D Class Discussion Topics 1. As a class, discuss how long an upgraded hardware and software components should be stored in case there is a need to back out and reinstall. What considerations should be taken into account when determining the appropriate time to discard old or upgrade equipment? 2. Documenting a network is essential in troubleshooting and support. Discuss the security implications in keeping such documentation. How should an organization balance access to the documentation against protecting the network from intentional hacking, compromise or damage? Additional Projects 1. Have the student research companies that specialize in the physical removal or destruction of data on hard disks. The research report should include information on three such companies including the company name, accurate Web site address (if available), physical location, services, and costs. 2. Have the student research network diagramming products on the market and write a report of their findings. The research should include three products and a comparison of the technical specifications, ease of use (if available), price, availability, and product ratings (if available). Additional Resources 1. Designing a Structured Cabling System http://www.cablinginstall.com/articles/print/volume-4/issue-1/contents/design/designing-a-structured-cabling-system-for-voice-and-data.html 2. Cisco Network Icons cisco.com/c/en/us/about/brand-center/network-topology-icons.html 3. Technology Asset Management http://www.tam-inc.com/ 4. TIA/EIA 568 Wiring Standard https://www.utm.edu/staff/leeb/568/568.htm 5. Five Free Apps for Diagraming a Network https://www.techrepublic.com/blog/five-apps/five-free-apps-for-diagramming-your-network/ Key Terms For definitions of key terms, see the Glossary near the end of the book.  110 block  66 block  crosstalk  demarc (demarcation point)  EIA (Electronic Industries Alliance)  EMI (electromagnetic interference)  entrance facility  fiber-optic cable  IDF (intermediate distribution frame)  inventory management  KVM (keyboard, video, and mouse) switch  licensing restrictions  MDF (main distribution frame or main distribution facility)  MLA (master license agreement)  MOU (memorandum of understanding)  MSA (master service agreement)  network diagram  Nmap  patch  patch management  patch panel  plenum  punchdown tool  PVC (polyvinyl chloride)  rack diagram  RFP (request for proposal)  rollback  SLA (service-level agreement)  SOW (statement of work)  STP (shielded twisted pair)  structured cabling  system life cycle  TIA (Telecommunications Industry Association)  upgrade  UTP (unshielded twisted pair)  VoIP (Voice over IP)  VoIP endpoint  VoIP gateway  VoIP PBX (private branch exchange)  wiki  wiring schematic Chapter 3 Addressing on Networks At a Glance Instructor’s Manual Table of Contents • Overview • Objectives • Teaching Tips • Quick Quizzes • Class Discussion Topics • Additional Projects • Additional Resources • Key Terms Lecture Notes Overview In this chapter, students learn the several methods used to address and find software, computers, and other devices on a network. They will take a bottom-up approach to the OSI model as they explore these topics, starting at the Data Link layer and working their way up to the Application layer. At the end of this chapter, they will learn how to troubleshoot addressing problems by using common command-line utilities. Chapter Objectives After reading this chapter and completing the exercises, the student will be able to: • Find the MAC address of a computer and explain its function in network communications • Configure TCP/IP settings on a computer, including IP address, subnet mask, default gateway, and DNS servers • Explain the purpose of ports and sockets, and identify the ports of several common network protocols • Describe domain names and the name resolution process • Use command-line tools to troubleshoot problems with network addresses Teaching Tips Addressing Overview 1. Give students a quick overview of the four addressing methods, starting at the bottom of the OSI model. • Data Link layer MAC address • Network layer IP address (IPv4 and IPv6) • Transport layer port numbers • Application layer FQDNs, computer names, and host names MAC Addresses 1. Describe where a student may physically find a NIC’s MAC address. Explain that students will later learn how to use TCP/IP utilities to find the MAC address. 2. Use Figure 3-1 to illustrate a NIC’s MAC address. 3. Describe the two components of a MAC address: a. OUI (Organizationally Unique Identifier) b. Device ID or extension identifier 4. Note the use of hexadecimal notation to represent the MAC address. 5. Explain how a student can determine which company manufactured a NIC by looking up its block ID if you know a computer’s MAC address. IP Addresses 1. Remind students that IP addresses identify nodes at the Network layer. 2. Explain the two types of IP addresses that can be assigned to a device: a. static IP address b. dynamic IP address 3. Discuss the use of a DHCP (Dynamic Host Configuration Protocol) server to manage dynamic distribution of IP addresses to devices on a network. 4. Lead students through the steps to view TCP/IP settings on a Windows 10 computer. 5. Discuss some of the settings students will view in the TCP/IP settings: a. gateway b. subnet mask c. DNS server 6. Point out that students can use the ipconfig utility in a Command Prompt window to find out the current TCP/IP settings. 7. Remind students that networks may use two types of IP addresses: IPv4 addresses and IPv6 addresses. IPv4 Addresses 1. Review the makeup of an IPv4 address. 2. Mention the two types of information an IP address may contain: network ID and host ID. Use Figure 3-5 in your discussion. 3. Describe the three types of network classes used for LANs in traditional IP addressing. Point out that these are called public IP addresses. 4. Use Table 3-1 to illustrate characteristics of the three commonly used classes of TCP/IP-based networks. 5. Mention the existence of Class D and Class E addresses and give an example of how they are used. 6. Use Table 3-2 to discuss reserved IP addresses. 7. Explain the use of the number 255 in broadcast transmissions. 8. Discuss dynamic IP address assignment using DHCP. 9. Walk students through the “Applying Concepts: Configure a DHCP Server” section of the text. 10. Define NAT (Network Address Translation) as a technique to conserve the number of public IP addresses needed by a network. Explain the difference between public IP addresses and private addresses. 11. Discuss the reasons why an administrator would choose to implement address translation. 12. Define and describe PAT (Port Address Translation). Use Figure 3-9 to illustrate an example of PAT usage. 13. Discuss the two variations of NAT that students should be aware of: a. SNAT (Static Network Address Translation). b. DNAT (Dynamic Network Address Translation) 14. Use Figure 3-10 to discuss the differences in SNAT and DNAT. 15. Discuss the “Applying Concepts: Configure Address Translation Using NAT” section with your students. IPv6 Addresses 1. Review the format of IPv6 addresses: a. 128 bits written as eight blocks of hexadecimal numbers separated by colons b. Each block is 16 bits c. Leading zeroes in a four-character hex block can be eliminated d. If blocks contain all zeroes, they can be eliminated and replaced by double colons. 2. Give examples of the proper way to use IPv6 shorthand notation for addresses. 3. Discuss the terms used in the IPv6 standard that students will need to be familiar with: a. link/local link b. interface c. dual stacked d. tunneling e. interface ID f. neighbors 4. Describe the three types of IP addresses supported by IPv6: • unicast • multicast • anycast 5. Use Figure 3-13 to discuss two types of unicast addresses: global and link local addresses. 6. Point out that IPv6 reduces network traffic by eliminating broadcasting. Use Figure 3-14 in your discussion. 7. Use Table 3-3 to discuss currently used address prefixes for IPv6 addresses. 8. Demonstrate using the ipconfig command to view addresses assigned to all network connections. Use Figure 3-15 to further demonstrate the output of the ipconfig command. 9. Describe the three steps involved in IPv6 autoconfiguration. Teaching Tip Students may find more information on IP addressing concepts at https://technet.microsoft.com/en-us/library/bb726995.aspx#EDAA Quick Quiz 1 1. True or False: Every host on a network is assigned a unique character-based name called the fully qualified domain name. Answer: True 2. The first 24 bits in a MAC address are known as which of the following? a. device ID b. OUI c. extension ID d. host ID Answer: B 3. The _____ is the gateway device that nodes on the network turn to first for access to the outside world. Answer: default gateway 4. Which of the following is a technique designed to conserve the number of public IP addresses needed by a network? a. public addressing b. NAT c. multicasting d. broadcasting Answer: B 5. IPv6 addresses are composed of ____ bits. a. 32 b. 64 c. 128 d. 256 Answer: C Ports and Sockets 1. Explain to students that a port is a number assigned to a process that can receive data and can be used to find a process running on that computer. 2. Use the example in the book to explain the use of a socket. For example, the standard port of the Telnet service is TCP 23. If a host has an IP address of 10.43.3.87, the socket address for Telnet running on that host is 10.43.3.87:23. 3. Use Figure 3-16 to demonstrate establishment of a session with the Telnet service. 4. Explain that port numbers range from 0 to 65535 and are divided into three types: a. Well known b. Registered ports c. Dynamic and/or Private Ports 5. Use Table 3-4 to illustrate commonly used TCP and UDP port numbers. 6. Take a moment to discuss some of the protocols that have yet to be covered in the book: a. TFTP b. NTP c. LDAP d. SMB e. SIP f. H.323 Teaching Tip Students may find more information on network ports used by key Microsoft Server products at: https://msdn.microsoft.com/en-us/library/cc875824.aspx Domain Names and DNS (Domain Name System) 1. Point out that host names and domain names were created because character-based names are easier for humans to remember than numeric IP addresses. 2. Remind students that a FQDN is a host name and a domain name together and the last part of an FQDN is called the TLD (top-level domain). 3. Define and explain how domain names are registered with an Internet naming authority. 4. Use Table 3-5 to illustrate some well-known top-level domains. 5. Introduce students to name resolution, which is the process of discovering the IP address of a host when its FQDN is known. Remind students that a computer must convert the FQDN to an IP address before it can find the reference computer. 6. Introduce and describe DNS (Domain Name System or Domain Name Service). 7. Define and describe the following: a. namespace b. name servers c. resolvers Namespace Databases 1. Compare a centralized database model to a distributed database model. Point out to students that DNS uses a distributed database model to store DNS namespaces. 2. Explain that an authoritative server is the authority on computer names and their IP addresses for computers in their domains. 3. Define and describe a DNS zone. Name Servers 1. Discuss the four common types of DNS servers: a. primary DNS server b. secondary DNS server c. caching DNS server d. forwarding DNS server 2. Use Figure 3-17 to demonstrate that name servers are organized in a hierarchical structure beginning with root servers. 3. Use Figure 3-18 as an example to illustrate domain name resolution. 4. Discuss a few ways the DNS process can get more complex. 5. Define and describe the two types of DNS requests: • recursive queries • iterative queries Resource Records in a DNS Database 1. Explain how resource records come in many different types, depending on their function. 2. Discuss the different types of resource records that an administrator should be familiar with: a. A (Address) record b. AAAA (Address) record c. CNAME (Canonical Name) record d. PRT (Pointer) record e. NS (Name Server) record f. MX (Mail Exchanger) record g. SRV (Service) record h. TXT (Text) record 3. Use Table 3-6 to discuss zone file records used to configure a DNS server. DNS Server Software 1. Point out that most popular DNS server software is BIND, which is free, open source software that runs on Linux, UNIX, and Windows platforms. 2. Use Figure 3-19 to discuss DNS services handled by two different servers so that the internal network remains protected. Teaching Tip Students may find more information on DNS at http://technet.microsoft.com/en-us/network/bb629410.aspx Troubleshooting Address Problems 1. Explain that Event Viewer is one of the first places to start looking for clues when something goes wrong with a computer. Use Figure 3-20 in your discussion Troubleshooting Tools 1. Define and explain ping (Packet Internet Groper). 2. Explain how ping uses ICMP services. 3. Note that an IP address or a host name may be pinged (see ping command options and parameters in Table 3-7). 4. Use Table 3-7 to describe the different ping command options, switches, and the syntax of the command. 5. Discuss the two variations of ping using ICMPv6. Use Figure 3-23 in your discussion. Teaching Tip Students may find more information about the ping utility at http://ipaddressguide.com/ping 6. Define and explain the ipconfig utility. a. Review the command switches. b. Note that this command operates with Windows-based systems. 7. Use Table 3-8 to discuss some of the options that can be used with the ipconfig command. Teaching Tip Students may find more information on the syntax and options for using the ipconfig diagnostic utility for network connections at https://technet.microsoft.com/en-us/library/bb490921.aspx 8. Define and explain the ifconfig utility. a. Review some command switches using Table 3-9. b. Note that ifconfig is the UNIX and Linux version of ipconfig. 9. Use Figure 3-26 to illustrate detailed information available through ifconfig. Teaching Tip Students may find more information on the syntax and options for the ifconfig command at https://www.computerhope.com/unix/uifconfi.htm 10. Define and explain the nslookup utility. a. Note that this utility is useful in troubleshooting DNS resolution problems. b. Use Figure 3-27 to illustrate the result of running a simple nslookup command. 11. Explain the two modes that are available in the nslookup utility: interactive and noninteractive. 12. Use Figure 3-29 to demonstrate the interactive mode of the nslookup utility. 13. Introduce students to the dig (domain information groper) utility. Point out that this utility is available on Linux and macOS and provides more detailed information than nslookup. 14. Use Table 3-10 to discuss some sample dig commands. Common Network Issues 1. Discuss some remedies for when a computer or device continues to show the wrong time after powering on. 2. Explain that if a DHCP server has set its lease time too long, the network tends to suffer from an exhausted DHCP scope. 3. Discuss how to view and change settings on a DHCP server. Use Figure 3-30 in your discussion. 4. Discuss some common network configuration errors: a. incorrect netmask b. incorrect gateway c. duplicate IP address Quick Quiz 2 1. HTTP uses which port number for requests between web servers and web clients? a. 23 b. 25 c. 68 d. 80 Answer: D 2. The last part of an FQDN is called the _______. a. host name b. domain name c. top-level domain d. resolver Answer: C 3. When a secondary DNS server needs to update its database, it makes a request to the primary server. This process is known as which of the following? a. zone transfer b. zone caching c. distributed database d. BIND Answer: A 4. Which type of DNS server is an optional server that receives queries from local clients but doesn’t work to resolve the queries? a. primary DNS server b. secondary DNS server c. caching DNS server d. forwarding DNS server Answer: D 5. True or False: The ipconfig utility is the TCP/IP configuration and management utility used on UNIX and Linux systems. Answer: False Class Discussion Topics 1. As a class, compare and contrast IPv4 and IPv6. 2. Ask students if IPv6 has been implemented at their workplace. Discuss whether they feel IPv6 will completely replace IPv4 or whether they feel IPv4 will remain in use for years to come. Additional Projects 1. Have each student research DHCPv6 and how it is used to serve up global IPv6 addresses to hosts that require static IP addresses. Students should write a report on their findings. 2. Have students research the dig utility and how it can be used to troubleshoot DNS issues. Students should write a report on their findings. Additional Resources 1. IBM TCP/IP RedBook http://www.redbooks.ibm.com/abstracts/gg243376.html 2. TCP/IP Fundamentals for Microsoft Windows: Overview http://technet.microsoft.com/en-us/library/bb726983.aspx 3. IPv6 http://www.worldipv6launch.org/infographic/ 4. IPv6 Addressing https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-r2-and-2008/dd458966(v%3dws.10) 5. Use Dig to Administer Windows DNS servers https://www.techrepublic.com/article/use-dig-to-administer-windows-dns-servers/ Key Terms For definitions of key terms, see the Glossary near the end of the book.  A (Address) record  AAAA (Address) record  address translation  anycast address  APIPA (Automatic Private IP Addressing)  authoritative server  broadcast  broadcast domain  caching DNS server  canonical name  classful addressing  CLI (command-line interface)  CNAME (Canonical Name) record  default gateway  device ID  DHCP (Dynamic Host Configuration Protocol)  DHCP pool  DHCP reservation  DHCP scope  DHCPv6  dig (domain information groper)  DKIM (DomainKeys Identified Mail)  DMZ (demilitarized zone)  DNAT (Destination Network Address Translation)  DNS (Domain Name System or Domain Name Service)  DNS zone  domain name  dual stacked  dynamic IP address  elevated Command Prompt  EUI-64 (Extended Unique Identifier-64)  exhausted DHCP scope  extension identifier  firewall  forward zone  forwarding DNS server  FQDN (fully qualified domain name)  gateway  global address  H.323  host ID  host name  IANA (Internet Assigned Numbers Authority)  ICANN (Internet Corporation for Assigned Names and Numbers)  ICMP (Internet Control Message Protocol)  ICMPv6  ifconfig  interface  interface ID  IP exclusion  IP reservation  IPAM (IP address management)  ipconfig  IPv4 (Internet Protocol version 4)  IPv6 (Internet Protocol version 6)  iterative query  LDAP (Lightweight Directory Access Protocol)  LDAPS (Lightweight Directory Access Protocol over SSL)  lease time  link  link local address  local link  loopback address  MAC reservation  MX (Mail Exchanger) record  multicast  multicast address  name resolution  NAT (Network Address Translation)  neighbors  netmask  network ID  node ID  NS (Name Server) record  nslookup (name space lookup)  NTP (Network Time Protocol)  octet  open source  OUI (Organizationally Unique Identifier)  PAT (Port Address Translation)  ping (Packet Internet Groper)  primary DNS server  private IP address  process  PTR (Pointer) record  public IP address  RA (router advertisement)  recursive query  registered port  resource record  reverse zone  root server  RS (router solicitation)  scope options  secondary DNS server  session  SIP (Session Initiation Protocol)  SMB (Server Message Block)  SNAT (Static Network Address Translation or Source Network Address Translation)  SPF (Sender Policy Framework)  socket  SRV (Service) record  static IP address  subnet  subnet ID  subnet mask  TFTP (Trivial File Transfer Protocol)  TLD (top-level domain)  TTL (Time to Live)  TXT (Text) record  tunneling  unicast address  well-known port  WSL (Windows Subsystem for Linux) Chapter 4 Network Protocols and Routing At a Glance Instructor’s Manual Table of Contents • Overview • Objectives • Teaching Tips • Quick Quizzes • Class Discussion Topics • Additional Projects • Additional Resources • Key Terms Lecture Notes Overview Chapter 4 focuses on how application data and instructions make the trip from one host to another at the Transport, Network, and Data Link layers. Students will learn how protocol messages are constructed at each of these layers, and they will explore the basics of how routers work, primarily at the Network layer. Finally, they will learn how to troubleshoot route issues between hosts. Chapter Objectives After reading this chapter and completing the exercises, the student will be able to: • Describe the functions of core TCP/IP protocols • Identify how each protocol’s information is formatted in a TCP/IP message • Explain how routers manage internetwork communications • Employ various TCP/IP utilities for network discovery and troubleshooting Teaching Tips TCP/IP Core Protocols 1. Emphasize that TCP/IP is a suite of specialized protocols and provide examples. 2. Use Figure 4-1 to review what occurs at each layer as data is exchanged between a browser and a Web server. 3. Define and describe connectivity devices. Explain that a device is known by the topmost OSI layer header it reads and processes. Use Figure 4-2 in your discussion. TCP (Transmission Control Protocol) 1. Remind students that TCP operates in the Transport layer and provides reliable data delivery services. 2. Explain characteristics of the Transport layer that affect TCP transmissions: a. connection-oriented b. sequencing and checksums c. flow control 3. Use Figure 4-3 to illustrate the format of a TCP segment. 4. Explain how the entire segment becomes data portion of an IP message. 5. Use Table 4-1 to describe the fields belonging to the TCP segment. 6. Explain that TCP uses a three-way handshake to establish a session before sending any data. Use Figure 3-4 to illustrate how a TCP connection is established. 7. Describe the contents of the three segments (SYN, SYN/ACK, and ACK) transmitted. UDP (User Datagram Protocol) 1. Introduce UDP (User Datagram Protocol) and point out that it does not guarantee delivery of data and no connection is established by UDP before data is transmitted. 2. Mention that UDP’s lack of sophistication makes it more efficient and faster than TCP. 3. Describe a situation that makes UDP useful. 4. Use Figure 4-6 to illustrate the format of a UDP segment. 5. Contrast the UDP segment in Figure 4-6 with the much larger TCP segment in Figure 4-3. IP (Internet Protocol) 1. Introduce IP (Internet Protocol) and describe its purpose. Be sure to mention the layer of the OSI model in which it operates. 2. Remind students that at the Network layer of the OSI model, data is formed into packets. Explain the purpose of the IP packet. 3. Discuss the characteristics of the IP protocol. Point out that there are two versions of IP used on networks today. 4. Use Figure 4-7 to illustrate the format of an IPv4 packet. 5. Use Table 4-3 to describe the fields in an IPv4 packet. 6. Explain to students that due to the added information an IPv6 packet carries, it uses a different format than IPv4. 7. Use Figure 4-9 to illustrate the format of an IPv6 packet, and figure 4-10 to illustrate an example of an IPv6 packet header. 8. Ensure students understand the length and other structural differences between IPv4 and IPv6 packets. Uses Tables 4-3 and 4-5 in your discussion. Teaching Tip For an in-depth comparison of IPv4 and IPv6, visit: https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_71/rzai2/rzai2compipv4ipv6.htm ICMP (Internet Control Message Protocol) 1. Introduce ICMP (Internet Control Message Protocol) and describe its purpose. 2. Describe the types of errors ICMP may report. 3. Emphasize that ICMP cannot correct the errors it reports. Those functions are left to higher-layer protocols, such as TCP. 4. Point out that just as there are two version of IP, there are also two versions of ICMP: ICMPv4 and ICMPv6. ARP (Address Resolution Protocol) 1. Introduce ARP (Address Resolution Protocol) and explain that it is used to maintain a database that maps local IP addresses to MAC addresses. 2. Define an ARP table and describe how it helps ARP operate efficiently. 3. Use Figure 4-12 to illustrate what an ARP table might look like. 4. Introduce the two types of entries an ARP table can contain: a. Dynamic ARP table entries b. Static ARP table entries 5. Demonstrate how the ARP utility is accessed and the information the utility provides. Use Table 4-13 to show the results of using the arp –a command on a Windows workstation. Teaching Tip Students may find more information on Address Resolution Protocol (ARP) at https://technet.microsoft.com/en-us/library/cc940021.aspx Ethernet 1. Explain that Ethernet is the most popular network technology used on modern LANs and is considered the most important Data Link layer standard. 2. Point out that Ethernet II is the current Ethernet standard. Use Figure 4-14 and Table 4-8 to discuss the components of a typical Ethernet II frame. 3. Introduce students to the term MTU (maximum transmission unit), which is the largest size, in bytes, that routers will allow at the Network Layer. 4. Be sure to mention that there are a few notable exceptions to Ethernet frame size limitations: a. Ethernet frames on a VLAN can have an extra 4-byte field between Source address field and the Type field b. Some special-purpose networks use a proprietary version of Ethernet that allows for a jumbo frame Quick Quiz 1 1. At which layer of the OSI model is a packet encapsulated with its own header and trailer to create a frame? a. Layer 1 b. Layer 3 c. Layer 4 d. Layer 2 Answer: D 2. TCP (Transmission Control Protocol) operates in which layer of the OSI model? a. Physical b. Transport c. Network d. Data Link Answer: B 3. True or False: UDP provides error checking and sequencing. Answer: False 4. Which Network layer protocol reports on the success or failure of data delivery? a. ARP b. UDP c. ICMP d. TCP Answer: C 5. ARP relies on _____, which transmits simultaneously to all nodes on a particular network segment. Answer: broadcasting Routers and How They Work 1. Introduce students to the internetworking device known as a router. Explain that a router joins two or more networks and passes packets from one network to another. 2. Describe the tasks performed by all routers, as outlined on page 196. Also, go over the list of optional functions a router may perform. 3. Discuss the three various router categories: • Core/interior routers • Edge/border routers • Exterior routers 4. Use Figure 4-17 to illustrate the three different types of routers. 5. Note the use of inexpensive routers in the home and small office. Multilayer Switches 1. Define a Layer 3 switch as being capable of interpreting Layer 3 data and working much like a router. Point out the primary difference is the way the hardware is built. 2. Define a Layer 4 switch. Point out that a Layer 4 switch is also known as a content switch. 3. Describe the advantages and disadvantages of multilayer switches. Routing Tables 1. Define and describe a routing table. 2. Explain that a router has two or more network ports and each port connects to a different network. Point out that each network connection is assigned an interface ID. 3. Use Figure 4-18 and Table 4-9 to describe how routing tables may be used to find the best path for a message to take in order to reach its destination. Routing Path Types 1. Describe the two methods of directing network traffic: a. Static routing b. Dynamic routing The route Command 1. Explain that the route command allows you to view a host’s routing table. Point out that on a Windows-based system, use the command route print instead. Also, on a Cisco-brand router, use the command show ip route. Routing Metrics 1. Explain that routers consider properties of a route, or routing metrics, to determine the best path to a destination when various paths are available. 2. Discuss some examples of routing metrics used by routers: a. Hop count b. Theoretical bandwidth c. Latency d. Load e. MTU f. Routing cost g. Reliability h. Network topology Routing Protocols to Determine Best Paths 1. Define and describe the term best path. 2. Explain that a routing protocol is used to collect data about current network status and contribute to the selection of the best path. Be sure to point out that routing protocols are not the same as routable protocols, such as IP. 3. Define and describe: • administrative distance (AD) • convergence time • overhead 4. Use Table 4-10 to summarize some common routing protocols. Interior and Exterior Gateway Routing Protocols 1. Explain that routing protocols are classified as IGP or EGP. Discuss the differences between IGP and EGP routing protocols. Use Figure 4-19 in your discussion. 2. Introduce distance-vector routing protocols and explain how they work. Point out that RIP, RIPv2, and EIGRP are distance-vector protocols. 3. Introduce link-state routing protocols and explain how they work. Point out that OSPF and IS-IS are link-state routing protocols. 4. Mention that the only EGP currently in use is BGP. 5. Explain that OSPF is a link-state routing protocol designed as an improvement to RIP. Point out that it can coexist with RIP or RIPv2 on a network. 6. Discuss the following characteristics of OSPF: a. supports large networks b. complex algorithms c. shared data d. low overhead, fast convergence e. stability f. multi-vendor routers 7. Explain how IS-IS (Intermediate System to Intermediate System) works. 8. Describe EIGRP as an advanced distance-vector protocol that combines some of the features of a link-state protocol and so is sometimes referred to as a hybrid protocol. 9. Point out that originally, EIGRP was proprietary to Cisco routers. While the standard was released to the public in 2013, EGIRP is still optimized for Cisco routers and is the preferred routing protocol on LANs that use Cisco routers exclusively. 10. Explain how BGP (Border Gateway Protocol) works. Discuss the following characteristics: a. path-vector routing protocol b. efficient c. customizable Troubleshooting Route Issues 1. Point out that TCP/IP comes with a complete set of utilities that can help track down most TCP/IP-related problems without using expensive software or hardware to analyze network traffic. Troubleshooting Tools 1. Remind students of the TCP/IP utilities they have already covered and introduce the following tools that can help discover information about a network. 2. Describe the netstat utility, which displays TCP/IP statistics and details about TCP/IP components and connections on a host. 3. Use Table 4-11 to discuss the netstat command options. Teaching Tip Students may read information on adding a GUI front end to the netstat command line utility at http://www.techrepublic.com/article/adding-a-gui-front-end-to-the-netstat-command-line-utility/ 4. Define and explain the tracert or traceroute utility. a. Note that the utility is known as tracert on Windows-based systems and traceroute on Linux, UNIX, and OS X systems. b. Walk through the steps traceroute takes to trace the path from one networked node to another. Use Figure 4-20 in your discussion c. Describe the simplest form of the traceroute command. 5. Use Table 4-12 to review traceroute and tracert command options. 6. Discuss reasons why a trace test might stop before reaching the destination. 7. Point out that a trace cannot detect router configuration problems or predict variations of routes over a period of time. 8. Define and describe the pathping utility. 9. Use Table 4-13 to review pathping command options. 10. Introduce students to the tcpdump utility, which is a free, command-line packet sniffer that runs on Linux and other Unix operating systems. 11. Point out that you must either use the sudo command or log in as root to access tcpdump. 12. Review tcpdump command options in Table 4-14. Solving Common Routing Problems 1. Use Table 4-15 to review all of the command-line utilities that have been covered so far. 2. Explain that interface errors occur when a logical connection between a node and a network is malfunctioning. 3. Discuss possible causes of interface errors, such as duplicate MAC addresses or MAC spoofing. 4. Discuss possible ways to troubleshoot hardware failures. 5. Define and describe neighbor discovery. Mention that IPv6 devices use NDP (Neighbor Discovery Protocol) in ICMPv6 messages to automatically detect neighboring devices. Quick Quiz 2 1. Which of the following devices joins two or more networks and passes packets from one network to another? a. Repeater b. Web server c. Router d. Hub Answer: C 2. Switches that operate anywhere between Layer 4 and Layer 7 are also known as ____or application switches. Answer: content switches 3. A technique in which a network administrator programs a router to use specific paths between nodes is known as which of the following? a. static routing b. routing protocol c. dynamic routing d. default gateway Answer: A 4. Which of the following routing metrics is a measure of the number of network segments crossed? a. latency b. hop count c. MTU d. cost Answer: B 5. Which of the following routing protocols are used by border routers and exterior routers to distribute data outside of an autonomous system? a. BGP b. RIP c. OSPF d. IS-IS Answer: A Class Discussion Topics 1. As a class, compare and contrast TCP and UDP. 2. Discuss the benefits of implementing IPv6 over IPv4. Additional Projects 1. Have student select five random companies, and issue the tracert or traceroute commands for each one. The student should prepare a report describing the results. Require the use of screen shots to back up the reported findings. 2. Have each student research available routers. The report should include a write-up for three to five devices. Included in the write-up should be a description of the device, including the manufacturer, the model, the seller, the cost, reviews, and a summary of the manufacturer specifications. Additional Resources 1. IBM TCP/IP RedBook http://www.redbooks.ibm.com/abstracts/gg243376.html 2. TCP/IP Fundamentals for Microsoft Windows: Overview http://technet.microsoft.com/en-us/library/bb726983.aspx 3. IPv6 http://www.worldipv6launch.org/ 4. IPv4 and IPv6 Technical Reference http://technet.microsoft.com/en-us/network/bb530961.aspx 5. How Routers Work http://computer.howstuffworks.com/router.htm Key Terms For definitions of key terms, see the Glossary near the end of the book.  AD (administrative distance)  ARP (Address Resolution Protocol)  ARP table  AS (autonomous system)  best path  BGP (Border Gateway Protocol)  border router  checksum  collision  collision domain  convergence time  core router  CSMA/CD (Carrier Sense Multiple Access with Collision Detection)  default route  distance-vector routing protocol  dynamic ARP table entry  dynamic routing  edge router  EGP (exterior gateway protocol)  EIGRP (Enhanced Interior Gateway Routing Protocol)  Ethernet II  exterior router  gateway of last resort  hop  hop limit  hybrid routing protocol  IGP (interior gateway protocol)  interior router  internetwork  IS-IS (Intermediate System to Intermediate System)  jumbo frame  latency  Layer 3 switch  Layer 4 switch  link-state routing protocol  MTU (maximum transmission unit)  neighbor discovery  netstat  OSPF (Open Shortest Path First)  packet sniffer  pathping  probe  protocol analyzer  RIP (Routing Information Protocol)  RIPv2 (Routing Information Protocol version 2)  route command  routing cost  routing metric  routing protocol  routing table  spoofing  static ARP table entry  static routing  tcpdump  three-way handshake  traceroute  tracert Instructor Manual for Network+ Guide to Networks Jill West, Tamara Dean, Jean Andrews 9781337569330, 9781133608196