Networks & Basic Concepts

Question 1

The “5 9’s” Rule

Answer 1

Availability of networks is expected to be 99.999% of the time. (5 minutes of downtime per year)

Question 2

Network Components: Client

Answer 2

Device end-user accesses the network with
Any device that connects to the network

Question 3

Network Components: Server

Answer 3

Provides resources to the rest of the network
Different servers = Different functions
Can be dedicated hardware/software or a device that is acting like a server for a particular function

Question 4

Network Components: Hub

Answer 4

Older tech to connect networked devices
Receives information in one port and rebroadcasts to all ports

Question 5

Network Components: Switch

Answer 5

Connects networked devices such as clients/servers.
Learn which devices are on which ports
Only forward traffic to destination port based on MAC
More security, efficiently uses bandwidth

Question 6

Network Components: Router

Answer 6

Connects two different networks together
Intelligently forwards traffic to/from a network based on its logical address
Most routers use IP to determine routing

Question 7

Network Components: Media

Answer 7

Connect two devices or a device to a port
Copper, fiber optic, WiFi (radio frequency)

Question 8

Network Components: WAN Link

Answer 8

Physically connects networks together
Examples: DSL, Cable, FIOS, Satellite, Cellular, Microwave

Connects internal networks to external networks

Question 9

Network Resources: Client/Server Model

Answer 9

Uses dedicated server to provide access to files, scanners, printers, & other resources
Administration & backup are easier since resources are on a few key servers

Question 10

Network Resources: Client/Server Benefits

Answer 10

Centralized administration
Easier management
Better scalability

Question 11

Network Resources: Client/Server Drawbacks

Answer 11

Higher cost
Requires dedicated resources
Requires network operating system

Question 12

Network Resources: Peer-to-Peer Model

Answer 12

Peers share resources with each other directly
Administration & backup are more difficult since resources are spread across many PCs

Question 13

Network Resources: Peer-to-Peer Benefits

Answer 13

Lower cost
No dedicated resources required
No specialized OS required

Question 14

Network Resources: Peer-to-Peer Drawbacks

Answer 14

Decentralized management
Inefficient for large networks
Poor scalability

Question 15

Network Geography: PAN

Answer 15

Personal Area Network
Smallest type of wires/wireless network
Covers least amount of area (few meters)

Bluetooth/USB to laptop/Firewire camera to computer

Question 16

Network Geography: LAN

Answer 16

Local Area Network
Connects components in limited distance
Each segment is limited to short distances (CAT5 = 100m)

Internal wired/wireless cards

Question 17

Network Geography: CAN

Answer 17

Campus Area Network
Connects building-centric LANs across a university, industrial park, or business park
Covers many square miles/buildings

College campus, business parks, military bases

Question 18

Network Geography: MAN

Answer 18

Metropolitan Area Network
Connects scattered locations across a city
Larger than CAN, but smaller than WAN
Up to 25-mile radius in larger cities

City departments (police), Community college with campuses spread across a county

Question 19

Network Geography: WAN

Answer 19

Wide Area Network
Connects geographically disparate internal networks
Leased lines or VPNs tunneled over the Internet
Covers distances around the country/world

Internet, connecting two private corporate networks