Unit 9 Network Fundamentals Living Online Unit 9 Network Fundamentals

Objectives Describe a network Explain the benefits of a network Identify risks in computing Describe the roles of clients & servers List & describe types of networks List & describe communications media & hardware Describe network security

Network 2 or more connected devices Can transfer data

Networks Benefits vs. Risks Benefits: Share information, collaborate, share hardware, share software, communication Risks: loss of autonomy, malicious code, network faults, setup & management costs, email is not private Benefits Risks

Why Hack? Theft of services Theft of Information Hatred & vengeance For the thrill of it Finds a way to get into password protected system to avoid paying for a service. Steal credit card info, national security data Some people hate companies or groups, so they try and destroy files or steal info to sell to opposing groups The thrill is seeing if they can break into it

Review T or F. Hackers invade other people’s computers only for fun. T or F. Software sharing is one of the benefits of networking. When you are on a network, you should assume that your email is not _____________? Private T or F. It is easier for a virus to spread on a network.

Network Types- Client-Server Server manages & provides a service to client Network OS Username & password Describe client-server with web page request example. Servers have network OS. Router or Hub

Network Types- Peer to Peer No server Small office or house Easy to set up

Network Types- LAN Local Area Network Small geographic area WLAN Office, school, house WLAN Wireless Need Wi-Fi card

Network Types- WAN Wide Area Network Large geographic area Two or more LANs connected by routers Big businesses with office around country or world Internet is biggest WAN Connected by fiber, satellites, telephone

Network Types- Internet Global network of connected, smaller networks World Wide Web & email are most popular

Network Types- Intranet Web based for internal company use Handbooks, manuals, employment forms, work news, etc Only can access from within that company Through web browser

Network Types- Extranet Similar to Intranet Outside users with user name & password can have access to internal info

Review How is the network at school different than your home one? How is it the same? Which type of network has an OS & requires a username/password for access? Client-server What are two popular Internet features? Email & Web At BK, you can access the Internet with your laptop & no wires. What type of network is this? WLAN

Communication Hardware- Modem Dial-Up Modem (Int or Ext) Modulate-demodulate Converts analog to digital & reverse Data over phone lines Dialed into a phone number SLOWWWWW Old- 300 bits per second (bps) or baud rate Now- 56k or kilobits per second

Comm. Hardware- Cable Modem Coaxial (Coax) cable High speed, always on Broadband 20Mbps (Megabits per second) Cable Modem

Comm. Hardware- DSL Modem Digital Subscriber Line High speed, always on Broadband Through phone lines 3Mbps Can use phone & Internet at same time Filters on phones

Comm. Hardware- Others ISDN (Old) T1 FiOS Faster than dial-up, over phone line T1 High speed for business (1.5Mbps) 24 copper or Fiber optic telephone line FiOS Similar to T1 Faster speeds Limited areas

Communication Hardware Router Connects computers Shares one Internet connection May allows wireless access Firewall Wireless Adapters or NIC

How They Connect

Review T or F. A modem converts analog to digital signals. T or F. Hackers invade other people’s computers only for fun. A _______ is confined to a limited geographical area. A _______ is made up of several local area networks. A _______ is a simple device that connects multiple computers together.

Who to Connect to? ISP Internet Service Provider Pay them (Comcast, Verizon)

ISP Services Dial-Up Broadband Wi-Fi Slow Telephone Lines High Speed Always On Cable, DSL, Satellite Cable, Phone, Dish/Air, Fiber Optics Wi-Fi Wireless access Public (Starbucks)

Speeds

Network Security Issues Control access to computer User name, passwords If none, unauthorized people can gain access & take/read valuable info OR change it so no one can use it Passwords Change often Use upper & lowercase letters, numbers, punctuation Not easy stuff Don’t write them down “cheat sheet” Broken mostly by shared ones or cheat sheets, not guessing

Network Security Issues Firewall Protects against unauthorized access to network from outside Antivirus Software Always be running, updating Wi-Fi Protection Use the security settings

Network Security Solutions Be careful who you hire People who don’t follow rules Back up data off-site Biometric security Fingerprint reader Voice pattern Retina scan

Review What device allows many PC’s to share a single, high-speed Internet connection? Router What are the companies called that charge you for Internet access? ISP What is the slowest Internet access method? Dial-Up

Unit 9 Network Fundamentals Living Online Unit 9 Network Fundamentals