# IT Fundamentals/2014/Networking

A computer network or data network is a telecommunications network that allows computers to exchange data. Networked computing devices pass data to each other in the form of packets across connections established using either cable or wireless media. This lesson covers computer networks, wireless networks, addressing, and shared resources.

## Objectives and Skills

Objectives and skills for the networking portion of IT Fundamentals certification include:
* Compare and contrast different methods of sharing and storage
** Local vs. hosted storage
*** File and print sharing
**** Workgroup
**** Homegroup
*** Network drives
*** Network attached storage
*** Direct attached storage
*** External hard drives
** Network vs. local printing
*** USB
*** Wireless / wired network
* Given a scenario, set up and configure a basic SOHO router (wired / wireless)
** Verify wired connection, if applicable
** Verify Internet connectivity

## Readings

* Wikipedia: Computer network
* Wikipedia: Wireless network
* Wikipedia: IP address
* Wikipedia: Shared resource

## Multimedia

* YouTube: IT Fundamentals - Basic Networking Devices
* YouTube: Introduction to Computer Networks Part 1 - Easy to understand basics
* YouTube: Introduction to Computer Networks Part 2 - Easy to understand basics
* YouTube: Introduction to Computer Networks Part 3 - Easy to understand basics
* YouTube: Introduction to Networking
* YouTube: Lecture - Networking
* YouTube: Lecture - OSI Model

## Activities

* Review Internet Archive: What is the Difference Between a Domain, a Workgroup, and a Homegroup. Compare and contrast different methods of sharing and storage between a domain, workgroup, and homegroup. On Windows, identify whether your system belongs to a domain, workgroup, or homegroup.
* Review IP address settings for your local network:
** Windows:
*** Review Microsoft: How do I fix network adapter problems? and Microsoft: Change TCP/IP Settings. Review network settings for your system.
*** Review ipconfig. Complete the activities to display IP address information, all information, and release and renew a dynamic IP address.
** OS X:
*** Review Apple: About Network Utility. Use Network Utility to review network settings for your system.
*** Review MacWorld: Configuring Your Mac's Network Settings Use System Preferences / Network to review network settings for your system. Use the Advanced button and TCP/IP settings to renew your DHCP lease.
*** Review Wikipedia: ifconfig. Use ifconfig to review network settings for your system.
** Linux:
*** Review YoLinux: Network GUI Configuration Tools. Use Network Configuration or System Settings / Networking to review network settings for your system.
*** Review Wikipedia: ifconfig. Use ifconfig to review network settings for your system. Review CyberCiti: Linux Force DHCP Client to Renew IP Address. Use dhclient to release and renew a dynamic IP address.
* Verify Internet connectivity:
** Verify a physical connection:
*** Wired: Check for connectivity lights on the network adapter and switch or router.
*** Wireless: Check for connectivity through the user interface.
** Verify ip address settings.
*** Windows: Use ipconfig.
*** OS X: Use Network Utility, System Preferences / Network, or ifconfig.
*** Linux: Use Network Configuration, System Settings / Networking, or ifconfig.
** Review Ping/Host. Verify local and remote connectivity using ping.
*** Ping your local IP address.
*** Ping your local default gateway address.
*** Ping an Internet host such as 8.8.8.8.
** Review Nslookup. Verify name resolution using nslookup and an Internet host name, such as en.wikiversity.org.
* Share a folder and connect to the shared folder:
** Windows GUI:
*** Review File Sharing Essentials. Share a folder on your system.
*** From another computer, use a UNC path to connect to the shared folder.
** Windows CLI:
*** Review Microsoft: Net Share. Use the net share command to share a folder on your system.
*** Review Microsoft: Net Use. From another computer, use the net use command to connect to the shared folder.
** OS X:
*** Review Apple: Mac Basics: File Sharing. Share a folder on your system.
*** Review Apple: Connect to Shared Computers and File Servers on a Network. From another computer, connect to the shared folder.
** Linux:
*** Review TechGage: Using Samba to Share Your Linux Folders. Install Samba if necessary and share a folder on your system.
*** Review HowToGeek: 3 Easy Ways to Connect to Windows Shared Folders from Linux. From another computer, connect to the shared folder.
* Play the GoCertify: OSI Networking game to practice matching protocols to their corresponding OSI layer.

## Lesson Summary

* A computer network or data network is a telecommunications network that allows computers to exchange data. Networked computing devices pass data to each other in the form of packets across connections established using either cable or wireless media.
* A network packet is a formatted unit of data sent through a network to the destination. Once packets arrive, they are reassembled into their original message.
* Wired media includes coaxial cable, twisted-pair cable, and optical fiber.
* Wireless local area network connections use spread spectrum technology based on a common flavor of open-standards wireless radio-wave technology defined as IEEE 802.11 and known as Wi-Fi.
* A network interface controller (NIC) is hardware that provides a computer with the ability to access the transmission media, and has the ability to process low-level network information.
* In Ethernet networks, each NIC has a unique 48-bit Media Access Control (MAC) address.
* A repeater or hub is an electronic device that receives a network signal in the form of bits, cleans it of unnecessary noise, and regenerates it. In local area networks, switches have replaced hubs.
* A bridge or switch is a device that connects and filters multiple network segments or devices, by forwarding data only to one or multiple devices that need to receive the data based on destination MAC address.
* A router is a device that forwards data packets between different computer networks based on network address (IP address).
* A modem is a device used to connect network nodes via wire not originally designed for digital network traffic, by modulating the digital signal to produce an analog signal for transmission.
* A firewall is a device used to control network security and access rules by rejecting access requests from unrecognized sources while allowing actions from recognized ones.
* An access point is a device that allows wireless devices to connect to a wired network using Wi-Fi, or related standards.
* An Internet Protocol address (IP address) is a numerical label assigned to each device participating in a network that uses the Internet Protocol for communication. An IP address serves two principal functions: host identification and network addressing.
* IP addresses are 32-bit (IPv4) or 128-bit (IPv6) numbers usually written and displayed in human-readable notations, such as 198.51.100.1 (IPv4), and 2001:db8:0:1234:0:567:8:1 (IPv6).
* IP addresses are assigned to a host either anew at the time of booting, or permanently by fixed configuration of its hardware or software. Persistent configuration is also known as using a static IP address. In contrast, in situations when the computer's IP address is assigned newly each time, this is known as using a dynamic IP address.
* Static IP addresses are manually assigned to a computer by an administrator.
* Dynamic IP addresses are assigned either by the computer interface or host software itself through automatic configuration, or assigned by a server using Dynamic Host Configuration Protocol (DHCP).
* A shared resource, or network share, is a computer resource made available from one host to other hosts on a computer network.
* Common network sharing protocols include Server Message Block (Windows, OS X, Unix-like), Apple File Protocol (OS X), and Network File System (Unix-like).
* In SOHO networks, a decentralized approach is often used, where every user may make their local folders and printers available to others. This approach is sometimes denoted as a workgroup or peer-to-peer network.
* In a workgroup, each computer is responsible for its own security, rather than relying on centralized authentication.
* Windows 7 and later Microsoft operating systems extend the workgroup with a homegroup option that uses a password to join computers into the group, and allows users' libraries, along with individual files and folders, to be shared between multiple computers.
* In larger networks, a centralized file server or print server, sometimes denoted client–server network, is typically used. A client process on the local user computer takes the initiative to start the communication, while a server process on the file server or print server remote computer passively waits for requests to start a communication session.
* The centralized authentication approach used in larger networks is referred to as a domain, where all user accounts, computers, printers and other security principals, are registered with a central directory service.
* In very large networks, a Storage Area Network (SAN) approach to shared resources may be used in addition to file and print servers.
* ipconfig is a Microsoft Windows console application that displays all current TCP/IP network configuration values and can modify Dynamic Host Configuration Protocol DHCP and Domain Name System DNS settings.
* ifconfig is a system administration utility in Unix-like operating systems that has features for configuring, controlling, and querying TCP/IP network interface parameters.
* ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol (IP) network and to measure the round-trip time for messages sent from the originating host to a destination computer.
* nslookup is a network administration command-line tool available for many computer operating systems for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record.
* net share is a Microsoft Windows command that manages shared resources.
* net use is a Microsoft Windows command that connects a computer to or disconnects a computer from a shared resource, or displays information about computer connections.

## Key Terms
### DHCP (Dynamic Host Configuration Protocol)

    A standardized network protocol used on Internet Protocol (IP) networks for dynamically distributing network configuration parameters, such as IP addresses for interfaces and services.

### directory service

    A software system that stores, organizes, and provides access to operating system information.

### DNS (Domain Name Services or Domain Name Server)

    A hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network.

### Ethernet

    A family of computer networking technologies for local area networks (LANs) and metropolitan area networks (MANs) standardized in 1983 as IEEE 802.3.

### IP (Internet Protocol)

    The principal communications protocol in the Internet protocol suite for routing / relaying datagrams across network boundaries.

### IP address

    A numerical label assigned to each device in a computer network that uses the Internet Protocol for communication.

### LAN (Local Area Network)

    A computer network that interconnects computers within a limited geographic area such as a home, school, computer laboratory, or office building.

### MAC address

    A unique identifier assigned to network interfaces for communications on the physical network segment.

### protocol

    A system of digital rules for data exchange within or between computers.

### SAN (Storage Area Network)

    A dedicated network that provides access to consolidated, block level data storage.

### TCP (Transmission Control Protocol)

    A core protocol of the Internet Protocol Suite that provides reliable, ordered, and error-checked delivery of a stream of octets between applications running on hosts communicating over an IP network.

### TCP/IP (Transmission Control Protocol / Internet Protocol)

    The computer networking model and set of communications protocols used on the Internet and similar computer networks.

### topology

    The arrangement of the various elements (links, nodes, etc.) of a computer network.

## Review Questions

* A computer network or data network is a _____. Networked computing devices pass data to each other in the form of _____ across connections established using _____. A computer network or data network is a telecommunications network that allows computers to exchange data. Networked computing devices pass data to each other in the form of packets across connections established using either cable or wireless media.
* A network packet is a ___. Once packets arrive, they are _____. A network packet is a formatted unit of data sent through a network to the destination. Once packets arrive, they are reassembled into their original message.
* Wired media includes _____, _____, and _____. Wired media includes coaxial cable, twisted-pair cable, and optical fiber.
* Wireless local area network connections use _____ technology based on a common flavor of open-standards wireless radio-wave technology defined as _____ and known as _____. Wireless local area network connections use spread spectrum technology based on a common flavor of open-standards wireless radio-wave technology defined as IEEE 802.11 and known as Wi-Fi.
* A network interface controller (NIC) is _____. A network interface controller (NIC) is hardware that provides a computer with the ability to access the transmission media, and has the ability to process low-level network information.
* In Ethernet networks, each NIC has a unique _____. In Ethernet networks, each NIC has a unique 48-bit Media Access Control (MAC) address.
* A repeater or hub is _____. In local area networks, hubs have been replaced by _____. A repeater or hub is an electronic device that receives a network signal in the form of bits, cleans it of unnecessary noise, and regenerates it. In local area networks, switches have replaced hubs.
* A bridge or switch is _____. A bridge or switch is a device that connects and filters multiple network segments or devices, by forwarding data only to one or multiple devices that need to receive the data based on destination MAC address.
* A router is _____. A router is a device that forwards data packets between different computer networks based on network address (IP address).
* A modem is _____. A modem is a device used to connect network nodes via wire not originally designed for digital network traffic, by modulating the digital signal to produce an analog signal for transmission.
* A firewall is _____. A firewall is a device used to control network security and access rules by rejecting access requests from unrecognized sources while allowing actions from recognized ones.
* An access point is _____. An access point is a device that allows wireless devices to connect to a wired network using Wi-Fi, or related standards.
* An Internet Protocol address (IP address) is _____. An IP address serves two principal functions: _____ and _____. An Internet Protocol address (IP address) is a numerical label assigned to each device participating in a network that uses the Internet Protocol for communication. An IP address serves two principal functions: host identification and network addressing.
* IP addresses are _____-bit (IPv4) or _____-bit (IPv6) numbers usually written and displayed in human-readable notations, such as _____ (IPv4), and _____ (IPv6). IP addresses are 32-bit (IPv4) or 128-bit (IPv6) numbers usually written and displayed in human-readable notations, such as 198.51.100.1 (IPv4), and 2001:db8:0:1234:0:567:8:1 (IPv6).
* IP addresses are assigned to a host either _____, or _____. IP addresses are assigned to a host either anew at the time of booting, or permanently by fixed configuration of its hardware or software. Persistent configuration is also known as using a static IP address. In contrast, in situations when the computer's IP address is assigned newly each time, this is known as using a dynamic IP address.
* Static IP addresses are assigned _____. Static IP addresses are assigned to a computer manually by an administrator.
* Dynamic IP addresses are assigned _____. Dynamic IP addresses are assigned either by the computer interface or host software itself through automatic configuration, or assigned by a server using Dynamic Host Configuration Protocol (DHCP).
* A shared resource, or network share, is _____. A shared resource, or network share, is a computer resource made available from one host to other hosts on a computer network.
* Common network sharing protocols include _____, _____, and _____. Common network sharing protocols include Server Message Block (Windows, OS X, Unix-like), Apple File Protocol (OS X), and Network File System (Unix-like).
* In SOHO networks, a decentralized approach is often used, where _____. This approach is sometimes denoted as a _____ or _____ network. In SOHO networks, a decentralized approach is often used, where every user may make their local folders and printers available to others. This approach is sometimes denoted as a workgroup or peer-to-peer network.
* In a workgroup, each computer is responsible for _____. In a workgroup, each computer is responsible for its own security, rather than relying on centralized authentication.
* Windows 7 and later Microsoft operating systems extend the workgroup with _____. Windows 7 and later Microsoft operating systems extend the workgroup with a homegroup option that uses a password to join computers into the group, and allows users' libraries, along with individual files and folders, to be shared between multiple computers.
* In larger networks, a centralized file server or print server, sometimes denoted _____, is typically used. A _____ process on the local user computer takes the initiative to start the communication, while a _____ process on the file server or print server remote computer passively waits for requests to start a communication session. In larger networks, a centralized file server or print server, sometimes denoted client–server network, is typically used. A client process on the local user computer takes the initiative to start the communication, while a server process on the file server or print server remote computer passively waits for requests to start a communication session.
* The centralized authentication approach used in larger networks is referred to as a _____, where all _____ are registered with _____. The centralized authentication approach used in larger networks is referred to as a domain, where all user accounts, computers, printers and other security principals, are registered with a central directory service.
* In very large networks, a _____ approach to shared resources may be used in addition to file and print servers. In very large networks, a Storage Area Network (SAN) approach to shared resources may be used in addition to file and print servers.
* ipconfig is _____. ipconfig is a Microsoft Windows console application that displays all current TCP/IP network configuration values and can modify Dynamic Host Configuration Protocol DHCP and Domain Name System DNS settings.
* ifconfig is _____. ifconfig is a system administration utility in Unix-like operating systems that has features for configuring, controlling, and querying TCP/IP network interface parameters.
* ping is _____. ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol (IP) network and to measure the round-trip time for messages sent from the originating host to a destination computer.
* nslookup is _____. nslookup is a network administration command-line tool available for many computer operating systems for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record.
* net share is _____. net share is a Microsoft Windows command that manages shared resources.
* net use is _____. net use is a Microsoft Windows command that connects a computer to or disconnects a computer from a shared resource, or displays information about computer connections.

## Assessments

* Flashcards: Quizlet: IT Fundamentals - Networking
* Quiz: Quizlet: IT Fundamentals - Networking

## See Also

* Network Fundamentals
* Computer Networks
* OSI model