# IT Fundamentals/2014/Internetworking

Internetworking is the practice of connecting a computer network with other networks through the use of routers that provide a common method of routing information packets between the networks.This lesson covers routers, network connections, and sharing and storage.

## Preparation

Learners should already be familiar with Network Fundamentals and IT Fundamentals/Networking.

## Objectives and Skills

Objectives and skills for the internetworking portion of IT Fundamentals certification include:
* Given a scenario, set up and configure a basic SOHO router (wired / wireless)
** Set WEP vs. WPA vs. WPA2
** Change SSID from default
** Apply a new wireless password
** Change admin password for router
** Connect to the new network
** Update firmware if necessary
* Compare and contrast cellular, wireless and wired data connections
** High vs. low mobility
** High vs. low availability
** High vs. low throughput/bandwidth
** High vs. low reliability
** Connection delay
** Number of concurrent connections
** Levels of security
* Compare and contrast different methods of sharing and storage
** HTTP vs. HTTPS
*** Browser-based file downloads
** FTP vs. FTPS vs. SFTP (Secure File Transfer Protocol)
** Local vs. hosted storage
*** Cloud-based services
**** Cloud-based collaborative applications
**** Cloud-based storage
** Peer-to-peer
*** Local adhoc network
**** Bluetooth sharing
*** Direct link (PC-to-PC)
*** Online peer-to-peer network

## Readings

* Wikipedia: Internetworking
* Wikipedia: Router (computing)
* Wikipedia: Wi-Fi
* Wikipedia: Internet service provider
* Wikipedia: File transfer
* Wikipedia: Peer-to-peer file sharing

## Multimedia

* YouTube: How the Internet Works in 5 Minutes
* YouTube: IT Fundamentals - Common Network Protocols
* YouTube: Configuring a SOHO Wireless Router
* YouTube: Understanding WEP, WPA, and WPA2
* YouTube: Wired vs Wireless Internet Speeds
* YouTube: What's the Difference Between HTTP and HTTPS?
* YouTube: P2P File Sharing

## Activities

* Set up and configure a basic wireless router using either a router emulator or your home router:
** Use a SOHO router emulator to set up and configure a basic wireless router. (Note: The emulator will not save configuration changes.):
*** Change the default administrator password for the device.
*** Configure wireless security by setting a new SSID name and setting the security mode to WPA2 with a strong password.
*** Research current firmware releases for the device. Locate the router's firmware upgrade page and review instructions from the router's Help page on how to update the firmware.
** Review settings for your home router:
*** Verify that the administrator password has been changed from the default.
*** Verify that the SSID security mode is set to WPA2 with a strong password.
*** Research current firmware releases for the device and determine whether a firmware update is required.
* Review Wikipedia: Wardriving. Use a free wireless scanner and scan your environment for wireless networks:
** Windows:
*** Review Archive: BitDreamers: Improve WLAN Signal Without Additional Tools on Windows.
*** Use the netsh wlan show networks mode=bssid command to scan for wireless networks.
** OS X:
*** Review AppStorm: How to Discover Any Network with iStumbler.
*** Download and install iStumbler and scan for wireless networks.
** Linux:
*** Review TuxMobil.org: Linux Wireless Sniffer.
*** Download and install a wireless scanner and scan for wireless networks.
** Android:
*** Review Google: farproc Wifi Analyzer.
*** Download and install Wifi Analyzer and scan for wireless networks.
** iOS:
*** Review WLANBook: Free WiFi Scanner for iPhone and iPad Without Jailbreak.
*** Download and install the Apple AirPort Utility and scan for wireless networks.
* Research plans available from different wired (cable, DSL) and wireless (cellular, wireless, satellite) Internet providers. Compare mobility, availability, bandwidth, reliability, delay, concurrent connections, security, and cost.
* Use a protocol analyzer to compare HTTP and HTTPS traffic:
** Review Wireshark and the lessons on how to:
*** Install Wireshark
*** Start a Wireshark Capture
*** Stop a Wireshark Capture
*** Capture Network Traffic
*** Filter Displayed Traffic
** Start a Wireshark capture and then use a browser to navigate to a website using HTTP, and another website using HTTPS.
** Stop the Wireshark capture.
** Filter for HTTP traffic and observe that the contents of the traffic are visible in the capture.
** Filter for HTTPS traffic and observe that the contents of the traffic are not visible in the capture.
* Compare FTP, FTPS, and SFTP:
** Review JScape: Understanding Key Differences between FTP, FTPS, and SFTP.
** Start a Wireshark capture and then use a browser or FTP client to navigate to an FTP site such as ftp://ftp.mozilla.org/pub/firefox/releases/ .
** Stop the Wireshark capture.
** Filter for FTP traffic and observe that the contents of the traffic are visible in the capture.
** If you regularly use FTPS or SFTP to connect to a server, capture a session and observe that the contents of that traffic are not visible in the capture.
* Review RIAA:About Piracy. Research legal issues and potential penalties related to illegal peer-to-peer file sharing.

## Lesson Summary

* Internetworking is the practice of connecting a computer network with other networks through the use of routers that provide a common method of routing information packets between the networks.
* A router connects two or more data lines from different networks, as opposed to a network switch, which connects data lines from a single network.
* A router has interfaces for different physical types of network connections, such as copper cables, optical fiber, or wireless transmission.
* A router contains firmware for different networking communications protocol standards, and the firmware should be updated whenever security or performance issues have been corrected.
* A router typically supports dynamic IP address assignment as either a DHCP client or DHCP server.
* A router may include a firewall, network address translation (NAT), VPN handling, and other security functions.
* WEP, WPA, and WPA2 are wireless network security protocols used to encrypt wireless traffic. WEP and WPA are no longer considered secure.
* Internet service providers provide services for accessing, using, or participating in the Internet using wired or wireless connections.
* Wired Internet connection options include twisted-pair phone lines, coaxial cable, and optical fiber cable. Wired connections have greater throughput/bandwidth, reliability, and availability.
* Wireless Internet connection options include Wi-Fi, cellular, and satellite. Wireless connections have high mobility, but suffer from increased latency in data transfer and more security risks.
* File transfer is a generic term for the act of transmitting files over a computer network.
* File transfer protocols include HTTP, HTTPS, FTP, FTPS, and SFTP. HTTP and FTP are clear-text protocols, which allow anyone to capture and view the network traffic. HTTPS, FTPS, and SFTP use cryptographic protocols (SSL/TLS or SSH) to encrypt network traffic between the sender and receiver.
* Peer-to-peer file sharing typically uses applications specifically designed for this task, and may include Internet peers, local ad hoc networks, and Bluetooth connections.
* Peer-to-peer file sharing may have legal ramifications if copyrighted material is shared.

## Key Terms
### 802.11a

    A wireless networking standard operating in the 5 GHz band and supporting up to 54 Mbps data rates.

### 802.11ac

    A wireless networking standard operating in the 5 GHz band and supporting up to 1 Gbps data rates.

### 802.11b

    A wireless networking standard operating in the 2.4 GHz band and supporting up to 11 Mbps data rates.

### 802.11g

    A wireless networking standard operating in the 2.4 GHz band and supporting up to 54 Mbps data rates.

### 802.11n

    A wireless networking standard operating in the 2.4 GHz or 5 GHz band and supporting up to 600 Mbps data rates.

### ad hoc

    A decentralized wireless network that does not rely on a pre existing infrastructure, such as routers or access points in managed wireless networks.

### AES (Advanced Encryption Standard)

    A widely accepted data encryption standard using symmetric cryptography and supporting key lengths of 128, 192 and 256 bits which supersedes DES.

### availability

    The proportion of time a system is in a functioning condition.

### bandwidth

    The bit-rate of available or consumed information capacity expressed typically in metric multiples of bits per second.

### DMZ (demilitarized zone)

    A physical or logical subnetwork that contains and exposes an organization's external-facing services to a larger and untrusted network, usually the Internet.

### DSL (Digital Subscriber Line)

    A family of technologies that are used to provide internet access by transmitting digital data over telephone lines.

### FTP (File Transfer Protocol)

    An unencrypted standard network protocol that uses TCP ports 20 and 21 to transfer computer files from one host to another host.

### FTPS (File Transfer Protocol over Secure Sockets Layer)

    An extension of the File Transfer Protocol (FTP) that uses TCP port 990 and adds support for the Transport Layer Security (TLS) and the Secure Sockets Layer (SSL) cryptographic protocols.

### HTML (Hypertext Markup Language)

    The standard markup language used to create web pages.

### HTTP (Hypertext Transfer Protocol)

    An application protocol that uses TCP port 80 for distributed, collaborative, hypermedia information systems and the foundation of data communication for the World Wide Web.

### HTTPS (Hypertext Transfer Protocol over Secure Sockets Layer)

    An extension of the Hypertext Transfer Protocol (HTTP) that uses TCP port 443 and adds support for the Transport Layer Security (TLS) and the Secure Sockets Layer (SSL) cryptographic protocols.

### ISP (Internet Service Provider)

    An organization that provides services for accessing, using, or participating in the Internet.

### latency

    The time interval or delay between a source sending a packet and the destination receiving it.

### mobility

    The degree to which a computing device is able to be transported during normal usage.

### NAT (Network Address Translation)

    A methodology of remapping one IP address space into another by modifying network address information in Internet Protocol (IP) datagram packet headers while they are in transit across a traffic routing device.

### peer-to-peer

    A distributed application architecture that partitions tasks or work loads between equally privileged participants.

### port forwarding

    An application of network address translation (NAT) that redirects a communication request from one address and port number combination to another while the packets are traversing a network gateway, such as a router or firewall.

### proxy server

    A computer system or an application that acts as an intermediary for requests from clients seeking resources from other servers.

### QoS (Quality of Service)

    The ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow.

### range extender

    A device that takes an existing signal from a wireless router or wireless access point and rebroadcasts it to create a second network.

### redundancy

    The duplication of critical components or functions of a system with the intention of increasing reliability of the system.

### resiliency

    The ability to provide and maintain an acceptable level of service in the face of faults and challenges to normal operation.

### routing table

    Lists the routes to particular network destinations, and in some cases, metrics (distance, performance, or cost) associated with those routes.

### SFTP (Secure File Transfer Protocol)

    A network protocol that uses TCP port 22 to provide file access, file transfer, and file management functionalities designed as an extension of the Secure Shell protocol (SSH).

### SOHO (Small Office / Home Office)

    The category of business or cottage industry that typically involves from 1 to 10 workers.

### SSH (Secure Shell)

    A cryptographic network protocol that uses TCP port 22 for initiating secure text-based shell sessions on remote systems.

### SSID

    A unique identifier for a wireless LAN.

### SSL (Secure Sockets Layer)

    A cryptographic protocol designed to provide communications security over a computer network using asymmetric cryptography, superseded by Transport Layer Security (TLS).

### subnet

    A logically visible subdivision of an IP network.

### Telnet

    An application protocol that uses TCP port 23 to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection.

### throughput

    The rate of successful message delivery over a communication channel.

### TKIP (Temporal Key Integrity Protocol)

    A stopgap security protocol used in the IEEE 802.11 wireless networking standard, and used to replace WEP without requiring the replacement of legacy hardware. TKIP is no longer considered secure.

### TLS (Transport Layer Security)

    A cryptographic protocol designed to provide communications security over a computer network using asymmetric cryptography, and which superseded Secure Sockets Layer (SSL).

### URL (Uniform Resource Locator)

    A reference to a resource that specifies the location of the resource on a computer network and a mechanism for retrieving it.

### VPN (Virtual Private Network)

    Extends a private network across a public network, such as the Internet, allowing a computer or network-enabled device to send and receive data across shared or public networks as if it were directly connected to the private network.

### WAN (Wide Area Network)

    A network that covers a broad geographic area using leased telecommunication lines.

### WI-Fi (Wireless Fidelity)

    A local area wireless technology that allows an electronic device to participate in computer networking using 2.4 GHz and 5 GHz bands.

### WEP (Wired Equivalency Privacy)

    The original security algorithm for IEEE 802.11 wireless networks, and superseded by WPA. WEP is no longer considered secure.

### WLAN (Wireless Local Area Network)

    A wireless computer network that links two or more devices using a wireless distribution method within a limited area such as a home, school, computer laboratory, or office building.

### WPA (Wireless Protected Access)

    A wireless computer network security protocol based on TKIP.

### WPA2 (Wireless Protected Access 2)

    A wireless computer network security protocol based on AES.

### WPS (Wireless Protected Setup)

    A network security standard that attempted to allow users to easily secure a wireless home network using a PIN rather than long passphrases. WPS is no longer considered secure and should be disabled if possible.

## Review Questions

* Internetworking is _____. Internetworking is the practice of connecting a computer network with other networks through the use of routers that provide a common method of routing information packets between the networks.
* A router connects _____, as opposed to a network switch, which connects _____. A router connects two or more data lines from different networks, as opposed to a network switch, which connects data lines from a single network.
* A router has interfaces for _____, such as _____, _____, or _____. A router has interfaces for different physical types of network connections, such as copper cables, optical fiber, or wireless transmission.
* A router contains firmware for _____, and the firmware should be _____. A router contains firmware for different networking communications protocol standards, and the firmware should be updated whenever security or performance issues have been corrected.
* A router typically supports dynamic IP address assignment as either _____ or _____. A router typically supports dynamic IP address assignment as either a DHCP client or DHCP server.
* A router may include _____, _____, _____, and other security functions. A router may include a firewall, network address translation (NAT), VPN handling, and other security functions.
* WEP, WPA, and WPA2 are _____. WEP and WPA are _____. WEP, WPA, and WPA2 are wireless network security protocols used to encrypt wireless traffic. WEP and WPA are no longer considered secure.
* Internet service providers provide services for _____. Internet service providers provide services for accessing, using, or participating in the Internet using wired or wireless connections.
* Wired Internet connection options include _____, _____, and _____. Wired connections have greater _____, _____, and _____. Wired Internet connection options include twisted-pair phone lines, coaxial cable, and optical fiber cable. Wired connections have greater throughput/bandwidth, reliability, and availability.
* Wireless Internet connection options include _____, _____, and _____. Wireless connections have high _____, but suffer from _____ and _____. Wireless Internet connection options include Wi-Fi, cellular, and satellite. Wireless connections have high mobility, but suffer from increased latency in data transfer and more security risks.
* File transfer is _____. File transfer is a generic term for the act of transmitting files over a computer network.
* File transfer protocols include _____. _____ are clear-text protocols, which allow anyone to capture and view the network traffic. _____ use cryptographic protocols (SSL/TLS or SSH) to encrypt network traffic between the sender and receiver. File transfer protocols include HTTP, HTTPS, FTP, FTPS, and SFTP. HTTP and FTP are clear-text protocols, which allow anyone to capture and view the network traffic. HTTPS, FTPS, and SFTP use cryptographic protocols (SSL/TLS or SSH) to encrypt network traffic between the sender and receiver.
* Peer-to-peer file sharing typically uses _____, and may include _____, _____, and _____ connections. Peer-to-peer file sharing typically uses applications specifically designed for this task, and may include Internet peers, local ad hoc networks, and Bluetooth connections.
* Peer-to-peer file sharing may have legal ramifications if _____. Peer-to-peer file sharing may have legal ramifications if copyrighted material is shared.

## Assessments

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

## See Also

* Network Fundamentals
* Introduction to Networking
* Computer Networks
* SANS: A Guide to Wardriving and Detecting Wardrivers