This document provides an overview of network naming protocols, including DNS and WINS. It describes:
1) How DNS evolved from the HOSTS file to become the main name resolution protocol on the internet, allowing names to be converted to IP addresses and vice versa in a hierarchical naming structure.
2) Additional details on how DNS works, including name spaces, name servers, name resolution, and examples of DNS configurations.
3) A brief introduction to WINS, which provides name resolution for legacy NetBIOS names to support backward compatibility in Windows networks.
4) How DNS and WINS can be used together, as well as tools for diagnosing and troubleshooting TCP/IP networks.
The document discusses several common TCP/IP applications including HTTP, HTTPS, Telnet, email protocols like SMTP, POP3 and IMAP4, and FTP. It describes the functions of each application, the port numbers they use, how clients and servers communicate over the network, and examples of client and server software.
The document describes the OSI 7-layer model and how it can be used to understand network communication. It explains each of the 7 layers, including the physical, data link, network, transport, session, presentation and application layers. Examples are provided to illustrate how data moves through each layer of the OSI model when transferring a file between two computers on a network.
This document discusses advanced networking devices and concepts. It covers four logical network topologies: client/server, peer-to-peer, virtual private network (VPN), and virtual local area network (VLAN). It also discusses trunking between switches and quality of service (QoS) policies for prioritizing network traffic. Home routers are highlighted as combining switch and router functionality into one advanced device that can operate at multiple layers of the OSI model.
Ethernet is a standard for network technologies that share a bus topology and frame format. Early Ethernet implementations transferred data at speeds up to 10Mbps using coaxial cable or twisted pair cabling. 10BaseT networks used twisted pair cabling and hubs to connect computers in a star topology up to 100 meters apart. Switches were later introduced to avoid bandwidth limitations of hubs by creating point-to-point connections between communicating devices using MAC addresses. This increased overall network speed and allowed larger, more complex network topologies.
The Network File System (NFS) is the most widely used network-based file system. NFS’s initial simple design and Sun Microsystems’ willingness to publicize the protocol and code samples to the community contributed to making NFS the most successful remote access file system. NFS implementations are available for numerous Unix systems, several Windows-based systems, and others.
This document provides an overview of connecting to and using the internet, including:
- Common internet connection methods like modem, DSL, and cable
- IP addressing and protocols like TCP/IP, HTTP, FTP, and email protocols
- Configuring internet applications like Internet Explorer and Outlook Express
- Troubleshooting tips for common internet issues
This document discusses securing TCP/IP networks. It covers four main areas of TCP/IP security: encryption, non-repudiation, authentication, and authorization. Encryption involves scrambling data so it can only be unscrambled by the intended recipient. Common encryption standards discussed include asymmetric key algorithms which allow secure key exchange. Secure TCP/IP applications then use these standards and tools to protect data in transit, such as HTTPS which uses SSL/TLS encryption for web traffic security.
The document discusses cabling and network topology. It describes different types of network topologies like bus, ring, star, mesh and point-to-point. It also discusses different types of cabling used in networks like coaxial cable, twisted pair cable, fiber optic cable and other cables. It provides details on IEEE standards for networking technologies and cabling.
The document discusses several common TCP/IP applications including HTTP, HTTPS, Telnet, email protocols like SMTP, POP3 and IMAP4, and FTP. It describes the functions of each application, the port numbers they use, how clients and servers communicate over the network, and examples of client and server software.
The document describes the OSI 7-layer model and how it can be used to understand network communication. It explains each of the 7 layers, including the physical, data link, network, transport, session, presentation and application layers. Examples are provided to illustrate how data moves through each layer of the OSI model when transferring a file between two computers on a network.
This document discusses advanced networking devices and concepts. It covers four logical network topologies: client/server, peer-to-peer, virtual private network (VPN), and virtual local area network (VLAN). It also discusses trunking between switches and quality of service (QoS) policies for prioritizing network traffic. Home routers are highlighted as combining switch and router functionality into one advanced device that can operate at multiple layers of the OSI model.
Ethernet is a standard for network technologies that share a bus topology and frame format. Early Ethernet implementations transferred data at speeds up to 10Mbps using coaxial cable or twisted pair cabling. 10BaseT networks used twisted pair cabling and hubs to connect computers in a star topology up to 100 meters apart. Switches were later introduced to avoid bandwidth limitations of hubs by creating point-to-point connections between communicating devices using MAC addresses. This increased overall network speed and allowed larger, more complex network topologies.
The Network File System (NFS) is the most widely used network-based file system. NFS’s initial simple design and Sun Microsystems’ willingness to publicize the protocol and code samples to the community contributed to making NFS the most successful remote access file system. NFS implementations are available for numerous Unix systems, several Windows-based systems, and others.
This document provides an overview of connecting to and using the internet, including:
- Common internet connection methods like modem, DSL, and cable
- IP addressing and protocols like TCP/IP, HTTP, FTP, and email protocols
- Configuring internet applications like Internet Explorer and Outlook Express
- Troubleshooting tips for common internet issues
This document discusses securing TCP/IP networks. It covers four main areas of TCP/IP security: encryption, non-repudiation, authentication, and authorization. Encryption involves scrambling data so it can only be unscrambled by the intended recipient. Common encryption standards discussed include asymmetric key algorithms which allow secure key exchange. Secure TCP/IP applications then use these standards and tools to protect data in transit, such as HTTPS which uses SSL/TLS encryption for web traffic security.
The document discusses cabling and network topology. It describes different types of network topologies like bus, ring, star, mesh and point-to-point. It also discusses different types of cabling used in networks like coaxial cable, twisted pair cable, fiber optic cable and other cables. It provides details on IEEE standards for networking technologies and cabling.
DNS is used to resolve hostnames to IP addresses. It works on port 53 and uses a hierarchical structure with roots, top-level domains, and second-level domains. DHCP is used to dynamically assign IP addresses to clients on a network. It uses a four-step process (discover, offer, request, acknowledgement) to lease an IP address to a client for a specified duration. Both DNS and DHCP are important for networking and name resolution in Windows environments.
This document discusses how to configure DHCP on a server. It describes installing and configuring the ifconfig utility to assign IP addresses statically or dynamically from DHCP. It also explains how to install and configure the ISC DHCP server, including editing configuration files, starting the DHCP service, and checking the firewall status.
This document provides an overview of routing and routers. It explains how routers work by forwarding packets based on destination IP addresses using routing tables. It describes dynamic routing protocols that allow routers to automatically share information and update routes. It also discusses installing and configuring routers through their web interfaces, serial connections, or network management software.
The document discusses the Domain Name System (DNS) which works to match domain names to IP addresses and vice versa. It describes how DNS was developed in the 1980s as the number of internet hosts grew dramatically. It also discusses DNS structure, name resolution methods, DNS queries, name server types, designing a good DNS, and DNS security issues. DNS is a critical service that binds internet servers worldwide by providing a distributed database for resolving domain names to IP addresses.
This document provides an overview of wireless networking standards and implementations. It describes how wireless networks use radio waves to communicate and follow the same OSI layers as wired networks. It outlines several IEEE 802.11 wireless standards including 802.11a, b, g, and n. It also discusses how Wi-Fi networks can operate in ad-hoc or infrastructure modes and how CSMA/CA is used to allow multiple devices to share the wireless medium. Finally, it covers common wireless security methods like MAC address filtering, wireless authentication, and data encryption using WEP.
Modern Ethernet standards include 100-megabit Ethernet, Gigabit Ethernet, and 10-Gigabit Ethernet. 100-megabit Ethernet standards include 100BaseT and 100BaseFX. Gigabit Ethernet standards include 1000BaseT, 1000BaseCX, 1000BaseSX and 1000BaseLX. 10-Gigabit Ethernet standards include 10GBaseSR, 10GBaseLR and 10GBaseER which use different fiber types and wavelengths, and 10GBaseT which uses copper cabling. Higher speeds require fiber optic cabling and support longer transmission distances.
The Internet originated as a way to connect computer networks globally in a resilient manner. It has since grown to be a worldwide system of interconnected computer networks that use standard communication protocols like TCP/IP to share data. The Internet provides many services like email, information search, online education, and entertainment. It connects billions of devices worldwide through internet service providers and uses protocols like HTTP, FTP, and SMTP to transfer different types of files and messages.
The document discusses network file systems (NFS) and its components. It describes how NFS allows remote access to shared file systems across networks using the NFS protocol. It explains the key aspects of NFS including exporting file systems from the NFS server, mounting remote file systems on clients, and the architecture involving NFS servers and clients. It also briefly mentions utilities like mountd, nfsd, and issues that can arise with user and group IDs when sharing files across systems.
This document discusses installing and troubleshooting physical networks. It covers:
1) Understanding structured cabling standards and components like patch panels, switches, and horizontal cabling.
2) The process of installing structured cabling which involves mapping runs, pulling cable, making connections, and testing.
3) Network interface cards (NICs) including different types, installation, and using link lights for troubleshooting.
4) Diagnosing and repairing cabling issues through methods like using cable testers, toners, and time domain reflectometers.
This document discusses setting up a Windows network, including installing network interface cards (NICs), hubs, switches, and access points. It covers installing networking software and configuring TCP/IP settings like IP addresses, subnet masks, and DNS servers in different versions of Windows. Key steps include installing the NIC and drivers, connecting devices to create the network infrastructure, and configuring the client software and TCP/IP properties to enable connectivity between PCs on the network.
This document discusses various technologies used for remote connectivity over wide area networks (WANs). It describes how analog signals were originally used for long-distance telephone calls but lost quality over distance, requiring the development of digital systems. Common digital WAN technologies discussed include SONET, T1, T3, cable modems, DSL, satellite, wireless, and fiber connections. Fiber networks are presented as a technology that telephone providers are implementing to compete with cable companies in providing high-speed internet to homes and businesses.
This document provides an introduction to web servers. It discusses how web servers work by responding to client requests over HTTP and mapping URLs to files on the server. Examples of popular web servers like Apache, IIS, and Tomcat are given. The document also gives a brief history of web servers and provides statistics on current market shares of different web servers. It describes accessing web servers locally or remotely via domain names or IP addresses. Finally, it discusses features of the IIS web server included with Windows and how to create virtual directories.
This chapter discusses configuring major network services on Linux servers including dynamic routing protocols, DNS servers, email servers, and web servers. It covers setting up routing protocols like RIP and OSPF, configuring the BIND DNS server software, setting up a sendmail email server, and using the Apache web server on Linux.
The document provides an overview of pfSense, an open source firewall and routing platform based on FreeBSD. It discusses the history and evolution of pfSense, hardware requirements, common deployment scenarios, and key features such as firewall rules, NAT, VPNs, traffic shaping, wireless access points, and high availability using CARP. The document also advertises a live demo of pfSense installation and configuration.
Serial data transmission uses one wire to carry data one bit at a time, while parallel uses multiple wires to carry a full byte at once. Common cable types include USB, FireWire, IDE, serial, and parallel. Cables have connectors on each end and internal wiring, and pinout diagrams identify each pin's purpose. Common connectors include D-Sub, Centronics, ribbon, RJ, and audio. Network cables include coaxial, twisted pair, and fiber optic varieties. Troubleshooting cables involves checking ports, testing with loopback plugs, and examining wires with a multimeter.
This document provides step-by-step instructions for installing and configuring the Koha library management system and migrating data. It outlines the process of installing Linux, setting up the required software including Koha, configuring parameters, and importing existing library data. The document is intended as a guide for libraries automating their systems and migrating to Koha.
The document provides an overview of TCP/IP basics, including how the Internet Protocol (IP) works. It describes IP addressing and how IP addresses are used to route packets within local area networks (LANs) and between LANs. The key points are:
1) IP addresses are 32-bit numbers that uniquely identify devices on a network. They allow communication between LANs by providing unique identifiers for each network and device.
2) Subnet masks are used to determine whether an IP address is local or remote. They define the network and host portions of an IP address.
3) Routers connect LANs and use IP addresses and routing tables to forward packets to the correct network.
The document discusses various types of network servers and their functions. It describes client-server and peer-to-peer network models. It also explains the roles of different servers like file servers, print servers, mail servers, database servers, and more. Network services like DNS, DHCP, and WINS are also summarized.
This document is a module from a Microsoft course on implementing DNS. It covers name resolution, installing a DNS server, and managing DNS zones. The key topics discussed include:
- How clients and servers resolve names using DNS, including the roles of DNS servers, zones, and records.
- Installing the DNS server role, including creating zones and configuring forwarding.
- Managing DNS zones, including the types of zones, dynamic updates, and Active Directory-integrated zones.
- Troubleshooting name resolution issues using tools like DNSCmd and Windows PowerShell cmdlets.
- A lab scenario instructing students to configure a domain controller as a DNS server, create host records, and set
DNS is used to resolve hostnames to IP addresses. It works on port 53 and uses a hierarchical structure with roots, top-level domains, and second-level domains. DHCP is used to dynamically assign IP addresses to clients on a network. It uses a four-step process (discover, offer, request, acknowledgement) to lease an IP address to a client for a specified duration. Both DNS and DHCP are important for networking and name resolution in Windows environments.
This document discusses how to configure DHCP on a server. It describes installing and configuring the ifconfig utility to assign IP addresses statically or dynamically from DHCP. It also explains how to install and configure the ISC DHCP server, including editing configuration files, starting the DHCP service, and checking the firewall status.
This document provides an overview of routing and routers. It explains how routers work by forwarding packets based on destination IP addresses using routing tables. It describes dynamic routing protocols that allow routers to automatically share information and update routes. It also discusses installing and configuring routers through their web interfaces, serial connections, or network management software.
The document discusses the Domain Name System (DNS) which works to match domain names to IP addresses and vice versa. It describes how DNS was developed in the 1980s as the number of internet hosts grew dramatically. It also discusses DNS structure, name resolution methods, DNS queries, name server types, designing a good DNS, and DNS security issues. DNS is a critical service that binds internet servers worldwide by providing a distributed database for resolving domain names to IP addresses.
This document provides an overview of wireless networking standards and implementations. It describes how wireless networks use radio waves to communicate and follow the same OSI layers as wired networks. It outlines several IEEE 802.11 wireless standards including 802.11a, b, g, and n. It also discusses how Wi-Fi networks can operate in ad-hoc or infrastructure modes and how CSMA/CA is used to allow multiple devices to share the wireless medium. Finally, it covers common wireless security methods like MAC address filtering, wireless authentication, and data encryption using WEP.
Modern Ethernet standards include 100-megabit Ethernet, Gigabit Ethernet, and 10-Gigabit Ethernet. 100-megabit Ethernet standards include 100BaseT and 100BaseFX. Gigabit Ethernet standards include 1000BaseT, 1000BaseCX, 1000BaseSX and 1000BaseLX. 10-Gigabit Ethernet standards include 10GBaseSR, 10GBaseLR and 10GBaseER which use different fiber types and wavelengths, and 10GBaseT which uses copper cabling. Higher speeds require fiber optic cabling and support longer transmission distances.
The Internet originated as a way to connect computer networks globally in a resilient manner. It has since grown to be a worldwide system of interconnected computer networks that use standard communication protocols like TCP/IP to share data. The Internet provides many services like email, information search, online education, and entertainment. It connects billions of devices worldwide through internet service providers and uses protocols like HTTP, FTP, and SMTP to transfer different types of files and messages.
The document discusses network file systems (NFS) and its components. It describes how NFS allows remote access to shared file systems across networks using the NFS protocol. It explains the key aspects of NFS including exporting file systems from the NFS server, mounting remote file systems on clients, and the architecture involving NFS servers and clients. It also briefly mentions utilities like mountd, nfsd, and issues that can arise with user and group IDs when sharing files across systems.
This document discusses installing and troubleshooting physical networks. It covers:
1) Understanding structured cabling standards and components like patch panels, switches, and horizontal cabling.
2) The process of installing structured cabling which involves mapping runs, pulling cable, making connections, and testing.
3) Network interface cards (NICs) including different types, installation, and using link lights for troubleshooting.
4) Diagnosing and repairing cabling issues through methods like using cable testers, toners, and time domain reflectometers.
This document discusses setting up a Windows network, including installing network interface cards (NICs), hubs, switches, and access points. It covers installing networking software and configuring TCP/IP settings like IP addresses, subnet masks, and DNS servers in different versions of Windows. Key steps include installing the NIC and drivers, connecting devices to create the network infrastructure, and configuring the client software and TCP/IP properties to enable connectivity between PCs on the network.
This document discusses various technologies used for remote connectivity over wide area networks (WANs). It describes how analog signals were originally used for long-distance telephone calls but lost quality over distance, requiring the development of digital systems. Common digital WAN technologies discussed include SONET, T1, T3, cable modems, DSL, satellite, wireless, and fiber connections. Fiber networks are presented as a technology that telephone providers are implementing to compete with cable companies in providing high-speed internet to homes and businesses.
This document provides an introduction to web servers. It discusses how web servers work by responding to client requests over HTTP and mapping URLs to files on the server. Examples of popular web servers like Apache, IIS, and Tomcat are given. The document also gives a brief history of web servers and provides statistics on current market shares of different web servers. It describes accessing web servers locally or remotely via domain names or IP addresses. Finally, it discusses features of the IIS web server included with Windows and how to create virtual directories.
This chapter discusses configuring major network services on Linux servers including dynamic routing protocols, DNS servers, email servers, and web servers. It covers setting up routing protocols like RIP and OSPF, configuring the BIND DNS server software, setting up a sendmail email server, and using the Apache web server on Linux.
The document provides an overview of pfSense, an open source firewall and routing platform based on FreeBSD. It discusses the history and evolution of pfSense, hardware requirements, common deployment scenarios, and key features such as firewall rules, NAT, VPNs, traffic shaping, wireless access points, and high availability using CARP. The document also advertises a live demo of pfSense installation and configuration.
Serial data transmission uses one wire to carry data one bit at a time, while parallel uses multiple wires to carry a full byte at once. Common cable types include USB, FireWire, IDE, serial, and parallel. Cables have connectors on each end and internal wiring, and pinout diagrams identify each pin's purpose. Common connectors include D-Sub, Centronics, ribbon, RJ, and audio. Network cables include coaxial, twisted pair, and fiber optic varieties. Troubleshooting cables involves checking ports, testing with loopback plugs, and examining wires with a multimeter.
This document provides step-by-step instructions for installing and configuring the Koha library management system and migrating data. It outlines the process of installing Linux, setting up the required software including Koha, configuring parameters, and importing existing library data. The document is intended as a guide for libraries automating their systems and migrating to Koha.
The document provides an overview of TCP/IP basics, including how the Internet Protocol (IP) works. It describes IP addressing and how IP addresses are used to route packets within local area networks (LANs) and between LANs. The key points are:
1) IP addresses are 32-bit numbers that uniquely identify devices on a network. They allow communication between LANs by providing unique identifiers for each network and device.
2) Subnet masks are used to determine whether an IP address is local or remote. They define the network and host portions of an IP address.
3) Routers connect LANs and use IP addresses and routing tables to forward packets to the correct network.
The document discusses various types of network servers and their functions. It describes client-server and peer-to-peer network models. It also explains the roles of different servers like file servers, print servers, mail servers, database servers, and more. Network services like DNS, DHCP, and WINS are also summarized.
This document is a module from a Microsoft course on implementing DNS. It covers name resolution, installing a DNS server, and managing DNS zones. The key topics discussed include:
- How clients and servers resolve names using DNS, including the roles of DNS servers, zones, and records.
- Installing the DNS server role, including creating zones and configuring forwarding.
- Managing DNS zones, including the types of zones, dynamic updates, and Active Directory-integrated zones.
- Troubleshooting name resolution issues using tools like DNSCmd and Windows PowerShell cmdlets.
- A lab scenario instructing students to configure a domain controller as a DNS server, create host records, and set
This document provides an overview of the Domain Name System (DNS). It discusses what DNS is, why names are used instead of IP addresses, and the history and development of DNS. It describes the hierarchical name space and domain system. It also explains different DNS record types like A, CNAME, MX, and NS records. The document discusses recursive and iterative queries, legal users of domains, and security issues with the traditional DNS system. It provides an overview of how DNSSEC aims to address some of these security issues through digital signing of DNS records.
This document discusses the Domain Name System (DNS) and how it maps human-friendly domain names to IP addresses. It explains that DNS information is stored in a distributed database and domain names are registered through registrars like Network Solutions. Various DNS record types are described, like A records for IP addresses and MX records for mail servers. Finally, common DNS tools are listed, such as whois, nslookup, and host, for looking up domain information and IP addresses.
1. The document discusses several protocols used to translate between different address types on a network, including DNS, DHCP, and ARP. DNS is a hierarchical and distributed system that maps hostnames to IP addresses. DHCP dynamically assigns IP configuration to hosts, while ARP maps IP addresses to MAC addresses for sending packets on the local link.
2. When a host first connects to the network, it uses DHCP to dynamically obtain its IP configuration including IP address, subnet mask, gateway, and DNS servers. It then uses ARP to discover the MAC address associated with destination IP addresses, allowing it to encapsulate IP packets for transmission on the link.
3. DNS uses a distributed database of name servers to lookup mappings between hostnames and
The document discusses the Domain Name System (DNS) which maps domain names to IP addresses. DNS uses a client-server model where clients (resolvers) query name servers to lookup addresses. It describes the hierarchical namespace structure and how names are organized into domains with labels separated by dots. Resource records containing domain, type, class and data are stored in distributed databases to map names and addresses. Caching improves performance by storing recent lookups.
This document provides an overview and lessons for a Microsoft course on implementing Domain Name System (DNS). It discusses DNS components and records, how name resolution works for Windows clients and servers, installing and managing a DNS server, and creating DNS zones. The key takeaways are how to install the DNS server role, configure zones and records, implement forwarding and caching, and tools for troubleshooting name resolution issues. Hands-on exercises demonstrate creating DNS records and zones and configuring a DNS server.
This document provides an overview of DHCP and DNS protocols. It discusses how DHCP can be used to automatically assign IP addresses and network configuration options to clients. DNS is used to map domain names to IP addresses and provides a distributed hierarchical database to store information about domain names. The document describes the basic components, operations, and implementations of both DHCP and DNS protocols.
Domain Name System (DNS) is the phone book of the Internet that translates human-readable domain names to IP addresses. DNS works through a distributed hierarchical system where DNS servers are authoritative for delegated zones. When an application needs to resolve a domain name to an IP address, the local DNS resolver queries other DNS servers iteratively until it finds the answer, caching responses for improved performance.
This document discusses DHCP and DNS protocols. DHCP is used to dynamically assign IP addresses to clients on a network. A DHCP server can assign addresses automatically from a pool, or assign specific addresses based on a client's MAC address. DNS is used to map domain names to IP addresses, allowing machines to be accessed by name rather than numeric address. DNS uses a distributed database across name servers to resolve names.
The document discusses the importance of DNS security for the internet. It provides background on the Domain Name System (DNS), explaining that DNS acts as the "phonebook" of the internet by translating domain names to IP addresses. While DNS was originally designed to be fault tolerant, dynamic, scalable, and redundant, security was not initially considered. The document outlines how DNS works and its hierarchical structure. It notes that traditional DNS uses UDP and lacks security features like authentication, making it vulnerable to spoofing and cache poisoning attacks. Finally, the document argues that DNSSEC is crucial for online safety as it uses digital signatures to authenticate DNS data and verify responses came from authorized servers.
The Domain Name System (DNS) provides translation between human-readable domain names and machine-readable IP addresses. DNS works like a phone book, allowing users to look up IP addresses using easier to remember domain names. DNS has a hierarchical structure with top-level domains at the root and subordinate domains below. DNS servers store and serve DNS records to resolve domain names to IP addresses through either iterative or recursive queries. Authoritative DNS servers maintain definitive records for their registered domains.
1. DNS resolves computer names to IP addresses through a hierarchical system of DNS servers and zones.
2. DNS servers contain DNS databases and resolve queries by providing the requested information directly or referring to other servers.
3. A DNS zone is a contiguous portion of the DNS namespace for which a DNS server is authoritative, containing domain records in zone files.
Internet Technology Lectures
URL-DNS
Lecturer: Saman M. Almufti / Kurdistan Region, Nawroz University
facebook: https://www.facebook.com/saman.malmufti
YouTube link: https://youtu.be/pOx04uODo5o
The Domain Name System (DNS) is a critical part of Internet infrastructure and the largest distributed Internet directory service. DNS translates names to IP addresses, a required process for web navigation, email delivery, and other Internet functions. However, the DNS infrastructure is not secure enough unless the security mechanisms such as Transaction Signatures (TSIG) and DNS Security Extensions (DNSSEC) are implemented. To guarantee the availability and the secure Internet services, it is important for networking professionals to understand DNS concepts, DNS Security, configurations, and operations.
This course will discuss the concept of DNS Operations in detail, mechanisms to authenticate the communication between DNS Servers, mechanisms to establish authenticity, and integrity of DNS data and mechanisms to delegate trust to public keys of third parties. Participant will be involved in Lab exercises and do configurations based on number of scenarios.
Domain Name System (DNS) - Domain Registration and Website Hosting BasicsAsif Shahzad
I teach Web Technologies course at COMSATS University to undergrad students. These are lectures slides prepared for students. I thought to share it with all. Hope you would like it. It contains good enough details about how DNS, Hosting and Domain Registration works.
The document discusses Domain Name System (DNS) servers and how they work. It provides information on:
1) DNS servers translate domain names to IP addresses so computers can locate systems on the internet. The DNS database hierarchy includes root servers, TLD servers, and authoritative name servers.
2) DNS uses a distributed database and client-server model. Root servers point to TLD servers, which point to authoritative servers that maintain records for domains.
3) DNS configuration files include named.conf, resolv.conf, zone files, and include files that define DNS settings and mappings.
This document discusses domain name system (DNS) configuration and troubleshooting. It describes DNS components like name servers, domains, and zones. It provides instructions for configuring DNS in Linux and Windows, including setting up primary and secondary servers with zone files. Troubleshooting tools like ping, nslookup, and dig are also covered.
This document provides an overview of deploying and configuring DNS service. It discusses the DNS architecture based on IP addresses and name resolution. The objectives of DNS are to assign host names without duplication, store the host name database across multiple servers to avoid bottlenecks, and create a standardized naming system. DNS has three main elements - the DNS name space organized in a tree structure with domains and resource records, name servers that contain information about domains and resource records, and resolvers which are client programs that generate queries to the name servers. The document explains how the DNS process works with queries being resolved through a series of DNS servers.
The document provides an overview of domain name servers (DNS) and their role in mapping domain names to IP addresses on the internet or private networks. It discusses DNS server hierarchy and the different types of DNS servers, including master, slave, caching-only and forwarding-only servers. It also defines terms like fully qualified domain name and the domains and sub-domains they contain. The document aims to introduce DNS concepts before explaining how to install and configure BIND, the most common DNS software on Linux systems.
This document summarizes key topics from Chapter 15 on recursion from the textbook "Starting Out with Java: From Control Structures through Data Structures". It discusses introduction to recursion, solving problems with recursion, examples of recursive methods, and the Towers of Hanoi problem. Recursion involves a method calling itself directly or indirectly. It is used to solve repetitive problems by reducing them to smaller instances until a base case is reached. Examples demonstrated include calculating factorials and Fibonacci numbers recursively.
This chapter discusses applets and HTML. It covers creating applets using Swing and AWT, drawing shapes, handling mouse/key events, and playing audio. Applets are Java programs that run in web browsers, while applications are standalone. Applets are inserted into HTML using <applet> tags and run on the user's computer, having restrictions on file/network access for security.
The document summarizes topics from Chapter 13 of a textbook on advanced GUI applications using Java Swing and AWT. It discusses read-only text fields, lists, combo boxes, displaying images, menus, text areas, sliders, and look and feel. Specific topics covered include creating lists from arrays, list selection modes, retrieving selected items, adding scroll bars to lists, combo box events, and displaying images in labels and buttons using the ImageIcon class.
This chapter discusses exceptions and advanced file input/output in Java, including:
- Handling exceptions using try/catch blocks and throwing custom exceptions
- Reading and writing binary files using DataInputStream and DataOutputStream
- Creating random access files for efficient reading/writing of data at specified locations
- Serializing Java objects to files to save their state for later use
This document discusses inheritance in Java. It covers key concepts like subclasses inheriting fields and methods from superclasses, the "is-a" relationship between classes, overriding methods, abstract classes and methods, and interfaces. Polymorphism is also discussed, where a reference variable can refer to objects of its type as well as subclasses.
This document summarizes Chapter 10 of the textbook "Starting Out with Java: From Control Structures through Data Structures" which discusses text processing and wrapper classes in Java. The chapter covers introduction to wrapper classes, the Character class for character testing and conversion, additional String methods for searching and extracting substrings, the StringBuilder class, and wrapper classes for numeric primitive data types. Example code is provided to demonstrate various string and character methods.
This chapter discusses static class members, passing and returning objects from methods, the toString and equals methods, copying objects, aggregation, the this reference, enumerated types, garbage collection, and object-oriented design principles. Key topics covered include defining static fields and methods, passing objects by reference, overriding toString and equals, creating "has-a" relationships between objects, and letting Java handle memory management through garbage collection.
This document provides an overview of key topics covered in Chapter 8, which discusses arrays and the ArrayList class. The chapter introduces arrays as collections of like values indexed in memory. It covers creating and initializing arrays, accessing array elements, and performing common operations on array contents such as finding highest/lowest values and averaging elements. The chapter also discusses passing arrays to methods, comparing arrays, and using arrays with files. It introduces the ArrayList class as an alternative to primitive arrays.
This chapter discusses graphical user interface (GUI) applications in Java. It introduces common GUI components like buttons, labels, text fields etc. It explains how to create windows and add components to them using Swing classes. It also covers layout managers which control component positioning and sizing, and event-driven programming where applications respond to user events like button clicks. The document provides examples of creating simple GUI applications in Java.
This chapter discusses classes and objects in Java. It explains that object-oriented programming centers on creating objects that contain both data fields and methods. A class defines the attributes and behaviors for a particular kind of object, acting as a blueprint. Individual objects are created from a class and are called instances of that class. The chapter demonstrates how to define a Rectangle class with fields for length and width, and methods to set, get, and calculate area. It also covers concepts like encapsulation, access modifiers, and the Unified Modeling Language (UML) for visually depicting classes.
The document discusses methods in Java. It explains that methods break problems into smaller pieces through functional decomposition. Methods simplify programs by allowing code to be reused. Methods can return values or be void. Arguments are passed into methods and parameters hold the values. Local variables only exist within methods. Methods are defined with a header and body. Comments should document a method's purpose. Exceptions must be handled or thrown by methods interacting with external resources like files.
This chapter discusses various types of loops in Java including while, do-while, and for loops. It covers the syntax and flow of each loop type as well as examples of using loops for input validation, running totals, and sentinel values. Nested loops are also introduced. The chapter then discusses break and continue statements before introducing file input/output.
The document summarizes topics from Chapter 3 of the textbook "Starting Out with Java: From Control Structures through Data Structures" including:
1) The chapter discusses Java control structures like if, if-else, nested if statements, logical operators, and comparing strings.
2) If statements and boolean expressions are used to conditionally execute code based on relational operators. Blocks of code can be executed with if-else statements.
3) Nested if statements allow if statements within other if statements so nested conditional logic can be implemented. Proper indentation and formatting helps readability of complex conditional statements.
This document summarizes Chapter 2 of a textbook on Java fundamentals. It discusses the parts of a Java program, including comments, classes, methods and statements. It also covers using print and println methods to output to the console and introduces concepts like variables, data types, operators and input/output.
The chapter discusses the history and components of computer systems and the Java programming language. It describes how Java was created to enable programs to run on various devices and operating systems. The chapter outlines computer hardware, including the central processing unit, memory, storage, and input/output devices. It also discusses operating systems, application software, programming languages, and how Java source code is compiled into bytecode that runs on the Java Virtual Machine across different computers.
This document discusses various tools used for network troubleshooting, including cable testers, protocol analyzers, multimeters, and software diagnostic tools. Cable testers like TDRs and OTDRs are used to identify cable breaks, while protocol analyzers monitor network activity at different layers. Software tools like ping, tracert, nslookup and dig help diagnose connectivity and DNS issues. The overall goal of troubleshooting is to analyze and resolve a variety of network problems using the appropriate tools.
IPv6 was developed to replace IPv4 due to IPv4's limited 32-bit address space and inefficient use of addresses. IPv6 supports 2128 addresses, improves security with IPSec, and uses more efficient routing through address aggregation. IPv6 addresses are 128-bit and written in hexadecimal, with groups of zeros represented by double colons. IPv6 implements subnet masks as CIDR prefixes between /48 and /64. It uses DNS clusters, global unicast addresses, and DHCPv6 to assign addresses and DNS servers to clients.
To successfully complete the course, students must:
1) Complete all module quizzes with a 70% or better, respond to discussion questions and posts from two classmates, and complete all module assignments.
2) Obtain a cumulative score of 70% from quizzes, assignments, exams, and class participation.
3) There are two exams - a midterm covering chapters 1-8 and a final exam covering chapters 9-16. The course uses two textbooks and grades are determined by labs, quizzes, exams and class participation.
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxEduSkills OECD
Iván Bornacelly, Policy Analyst at the OECD Centre for Skills, OECD, presents at the webinar 'Tackling job market gaps with a skills-first approach' on 12 June 2024
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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Find out more about ISO training and certification services
Training: ISO/IEC 27001 Information Security Management System - EN | PECB
ISO/IEC 42001 Artificial Intelligence Management System - EN | PECB
General Data Protection Regulation (GDPR) - Training Courses - EN | PECB
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Article: https://pecb.com/article
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Slideshare: http://www.slideshare.net/PECBCERTIFICATION
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
2. Objectives
• Describe the function and capabilities of DNS
• Configure and troubleshoot WINS
• Use common TCP/IP utilities to diagnose
problems with and WINS
4. Introduction to Naming
• Computers use IP addresses to communicate
• People remember names better than
numbers
• Name resolution created to convert names to
IP addresses (and vice versa)
5. • Name resolution has evolved over the years
• Main protocol is Domain Name System (DNS)
• Operating systems support old and new
• Windows, Linux, and Macintosh OS X still
support Windows Internet Name Server
(WINS)
9. DNS
• Early Internet use of HOSTS file
– One file copied to all hosts on the Internet
– Contained a list of IP addresses for every
computer, matched to system names
– Preceded rules for composing Internet
names
10. • HOSTS file
– Preceded DNS
– Anyone could name computer anything
– Duplicate names not allowed
– Sample old HOSTS file:
• 192.168.2.1 fred
• 201.32.16.4 SCHOOL2
• 123.21.44.16 SERVER
11. • HOSTS file
– Hosts file updated on every system every
morning at 2 a.m.
– Impractical after Internet grew to 5000
– New name system, but HOSTS file still
exists
– # symbol indicates a line is a comment
12. • HOSTS file
– Every OS first looks in HOSTS file
– Follow-up to Try This!
• Every TCP/IP app looks at HOSTS file
• If you altered the HOSTS file per the Try This!
enter this command:
ping timmy
13. • HOSTS file
– Some place shortcut names in a HOSTS file
to avoid typing a long name into browser
– DNS is more powerful and used much
more
14. • How DNS works
– No single computer can handle all Internet
name resolution
– Delegation used
• Top-dog DNS system delegates parts of the job
• Subsidiary DNS systems delegate parts of their
work
• All DNS servers run a special DNS server program
15. • How DNS works
– Naming system facilitates delegation
– Top-dog DNS a bunch of powerful systems
• Dispersed around the world
• Known collectively as the DNS root servers (or
DNS root)
– The Internet name for DNS root is “.”
– Below root are the top-level domain servers
16. • Name Spaces
– Hosts file uses a flat name space
– DNS uses a hierarchical name space
• A hierarchy of DNS domains and computer names
• Hierarchical DNS names space is the DNS Tree
• Root is the holding area to which all domains
connect
• Individual computers have host names
17. • Name Spaces
– Home-brewed DNS
• Must not connect to the Internet
• Set up a DNS server to be the root server
19. Figure 10.3 Two DATA.TXT files in different
directories on the same system
20. • Name Spaces
– DNS naming syntax
• Opposite of disk folder/directory syntax
• A complete DNS name is a fully qualified domain
name (FQDN)
• Host and all domains in order
• Root is far right
24. • Name Servers
– One server is authoritative DNS server for a
domain
• a.k.a. Start of Authority (SOA)
• Other name servers (NS) are subordinate
• All DNS servers know the address of SOA and all
NS servers in the domain
• SOA keeps others updated
25. • Name Servers
– Other systems send queries to DNS servers
– Request resolution of FQDNs to IP addresses
26. Figure 10.7 A single SOA can support one or
more domains
31. • Name Resolution
– DNS not required to access Internet
– DNS just makes is much easier
– IP addresses required for connections
– Most people would not use Internet without
DNS name resolution
32. • Name Resolution
– Type Web address into a browser
– It must resolve the name to IP address
– Three ways to resolve a name
• Broadcasting
• HOSTS file
• Querying a DNS server
33. Figure 10.12 Any TCP/IP-savvy program accepts
either an IP address or an FQDN
43. • DNS Servers (in action)
– Most OSs have built-in DNS server software
• Server versions of Windows
• Most versions of UNIX/Linux
– Third-party DNS servers
44. • DNS Servers (in action)
– Three special storage areas
• Cached Lookups
• Forward Lookup Zones
• Reverse Lookup Zones
49. • Totalhome domain example
– Does not comply with Internet rules
– None of the computers is visible on Internet
– Only usable on private network
– Forward lookup is named totalhome
– All the DNS servers listed under NS records
50. • Totalhome forward lookup zone
– Each system in the domain has an A record
– An alias for a system is a canonical name
(CNAME)
– SMTP servers use MX records (Mail eXchanger)
– AAAA records are for IPv6 addresses
56. • Windows DNS server
– Performs most functions exactly like
UNIX/Linux DNS servers
– Adds a Windows-only Active Directory-
integrated zone
– Avoids problems of standard DNS servers
– All domain controllers are DNS servers
– All DNS servers are equal
57. • Enter Windows
– 1980s Microsoft NetBIOS/NetBEUI
– 1990s Microsoft created NetBIOS over
TCP/IP – added NetBIOS naming to DNS
– Old sharing protocol Server Message Block
(SMB)
59. • Enter Windows—NetBIOS over TCP/IP
– New sharing protocol Common Internet File
System (CIFS)
– SMB/CIFS adopted by UNIX/Linux and Mac
OS X
– CIFS and DNS work together
60. Figure 10.30 Samba on Ubuntu (it’s so common that the OS
doesn’t even use the term in the dialog box)
61. • Living with the Legacy of CIFS
– Networks using CIFS use two name systems
– CIFS broadcast to find local server
– DNS query to find TCP/IP host
– CIFS and DNS work together
62. • Living with the Legacy of CIFS
– CIFS organizes computers into workgroups
– Computer joins a workgroup
– Flat name space
– See workgroups in Network/My Network
Places
65. • Living with the Legacy of CIFS
– Computers controlled by Windows domain
controller server are grouped in a Windows
domain
– Windows Computers join a domain
– Computers (and users) authenticate to the
domain
– Windows domains now use DNS naming
67. • Living with the Legacy of CIFS
– An Active Directory domain is an
organization of computers that shares one
or more Windows domains
– All Active Directory Windows domain
controllers are DNS servers
– All domain controllers are equal partners
68. Figure 10.34 If one domain controller goes down,
another automatically takes over
69. • Active Directory-Integrated Zones
– DNS system not reliant on a single server
– Windows DHCP servers automatically
update all client information in the Active
Directory-integrated zone
– In some cases the client updates DNS
– Non-Windows systems can only update
Activity Directory-Integrated Zones using a
Windows client (like Samba)
71. • Troubleshooting DNS
– Client is source of most DNS problems
– DNS servers rarely go down
– If a DNS server is down, clients use
secondary DNS server
– Symptom: “server not found” error
73. • Troubleshooting DNS
– Eliminate any local DNS caches
• Do not use Web browser for troubleshooting
• Run ipconfig /flushdns
• PING the name of a well-known Web site
– Does it return IP address?
– If not, PING an IP address
75. • Troubleshooting DNS
– If the previous steps indicate a problem with
the DNS server, run NSLOOKUP run
• Queries functions of DNS servers
• Depends on proper permission level
• Use to change how your system uses DNS
76. • Troubleshooting DNS
– Run NSLOOKUP without parameters to get
• IP address and name of default DNS server
• Error indicates primary DNS server is down or
client has wrong IP for DNS server
• NSLOOKUP has own prompt
77. • Troubleshooting DNS
– UNIX/Linux tool: domain information
grouper (DIG)
• Similar to NSLOOKUP
• Non-interactive
• Ask it a question; it answers
79. WINS
• Legacy NetBIOS
– Current versions of Windows use DNS
and/or CIFS
– NetBIOS names supported for downward
compatibility
– NetBIOS system broadcasts its name
80. • Prior to CIFS
– LMHOSTS file
• Works for NetBIOS like HOSTS does for DNS
• Microsoft OSs still support
• Every Windows systems has an LMHOSTS file
81. • Windows Internet Naming Service (WINS)
– WINS server for legacy Windows
– No broadcasting: NetBIOS hosts register
with WINS
– Allows NetBIOS to function in a routed
network
– WINS proxy agent for legacy Windows
84. • Configuring WINS clients
– Enter IP address of WINS server
– WINS information can be added to DHCP
– WINS clients register NetBIOS names with
WINS server
85. • Troubleshooting WINS
– Most “WINS” problems are NetBIOS
problems
• Two systems sharing same name
• Change name of one system
– NBTSTAT
• Check name cache with nbtstat –c
• Determine if WINS server has given inaccurate info
87. • Improper configuration causes most
problems
• PING anyone you want to connect to
• Regardless of what the user cannot
connect to, you perform the same steps
88. • Use common sense
– If one system behaves differently than others,
the problem is with the client
– Before starting steps (below) check the network
connections and protocols
89. • Steps for troubleshooting TCP/IP
– Diagnose the NIC
– Diagnose locally
– Check IP address and subnet mask
– Run NETSTAT with no options
– Run netstat –s
– Diagnose to the gateway
– Diagnose to the Internet
Teaching Tip If the students have access to computers with an Internet connection, have them take time to do the Try This on page 246. If their computers are running Windows, they will find the HOSTS file in the locations provided in the paragraph immediately above the exercise. However, they will only be successful if they have full access to the HOSTS file, including the ability to save it back to the same location. You may have to tinker with the permissions on the computers in order to allow the students to do this. If these are lab computers, and you are not permitted or inclined to change the security, then consider giving a demonstration. If you have full control of a computer with a projector connected, be prepared to simply demonstrate this on your computer. That will mean checking out the exercise before class. Now, the point of the exercise is that the HOSTS file may be archaic, but it is powerful in the right or wrong hands. There are good reasons why the recent versions of Windows protect this file so fiercely. A HOSTS file can be used to lock down a network, and it can also be used maliciously. I experienced both situations in computer training labs.
Teaching Tip If you have not done so, introduce the concept of name space here, but do not go into detail (it is a topic head later in the chapter). Point out that the HOSTS file came into being when the Internet had a flat name space, whereas DNS is a hierarchical name space. This is true, even though HOSTS files still work today.
Teaching Tip The Test-specific information begins here.
Teaching Tip The Tip on the bottom of Page 247 points out that DNS servers use TCP and UDP port 53. Teaching Tip Per Note on Page 247: “The DNS root for the entire Internet consists of 13 powerful DNS server clusters scattered all over the world.” Make sure the students understand that a cluster consists of many servers. Also, have them go to www.root-servers.org , or do so for them, and share the information you find there.
Teaching Tip The TRACERT command does a reverse lookup when you use an IP address rather than an FQDN. If you need to find the FQDN associated with an IP address, do a TRACERT on the address.