Section 1- Exploring Functions of Networking

Question 1

What are the devices at the bottom of a networking branch called?

Answer 1

Endpoint devices

Question 2

Name examples of endpoint devices

Answer 2

• PCs
• Laptops
• File servers
• Printers
• IP phones
• Sensors
• Cameras
• Manufacturing robots
• Are examples of ‘—’ devices at the end of a network branch

Question 3

Interconnections

Answer 3

Interconnections are…

components that connect devices on the network,

providing means for data to travel from

one point to another in the network.

Question 4

components that connect the devices on the network, providing a means for data to travel from one point to another in the network.

Name 3 interconnection components

Answer 4

1. NICs
2. Network media
3. Connectors

Question 5

NIC

1. Compound terms
2. What it does
3. Where it’s found
4. How it (physically) connects to a network

Answer 5

1. Network Interface Card/Controller
2. Translates computer data into format that can be transmitted over a network
3. On PC, laptop
4. A NIC is the device on a PC into which you plug a network cable.

Question 6

Network Media

1. What it does
2. Name the plural of ‘Media’

Answer 6

1. provide the means by which

signals are transmitted from

one network device to another

2. ‘Medium’

Question 7

Name 3 types of Network Media

Answer 7

1. Copper cabling
2. Fiber-optic cabling
3. Wireless connections

Question 8

Connectors

1. What type of component is this?
2. What it does
3. Name the most common network connector and number of wires it has

Answer 8

1. Interconnection component
2. Provides connection point for the media
3. RJ-45, 8

Question 9

Switches

1. Define
2. Devices that communicate via switch share a ‘—’ network
3. Can devices on switch communicate with other networks?

Answer 9

1. Allow endpoint devices to communicate directly with ea other
2. Common network
3. No, you need a router to communicate with outside networks

Question 10

What are 2 limitations of hubs compared to switches?

Answer 10

1. Performance
2. Speed
   - Are limitations to this device, compared to switches

Question 11

Routers

1. What they do
2. Their main function

Answer 11

1. connect networks and intelligently choose the best paths between networks
2. Their main function is to route traffic from one network to another
   - This network device is called…

Question 12

WLAN Devices

1. What do they connect?
2. Name 2 WLAN devices

Answer 12

1. Wireless devices to the network
2. a) NIC b) WLAN AP

Question 13

What are the 2 minimum requirements for wireless access to the network?

Answer 13

1. Device w/ a wireless NIC
2. WLAN AP (connected to traditional wired network)
   - are the 2 minimum requirements for this type of connection to a network

Question 14

APs

1. Compound Terms
2. What do they connect to?
3. Can also be an integrated component in what device?

Answer 14

1. Access Points
2. Allows wireless devices to connect to a wired network
3. Router

Question 15

Firewalls

1. Define
2. Establishes barrier between what two types of networks?

Answer 15

1. These devices are network security systems that

monitor and control the incoming and outgoing network traffic

based on predetermined security rules.

2. A trusted, secure internal network and an insecure, untrusted external network (i.e. the Internet)

Question 16

Multipurpose Device/ Router

1. Define
2. What 3 devices are integrated into a MpD/R?
3. Explain characteristics of 3 devices integrated into MpD/R

Answer 16

1. provides connectivity for wired and wireless devices as well as providing access to the Internet.
2. Switch, router, WLAN AP
3. Acts as a switch by providing physical ports to plug local devices into.

Acts as a WLAN AP by allowing wireless devices to connect to it.

Acts as a router by connecting the local network to the Internet.

Question 17

Name the 7 Characteristics of Networks

Answer 17

1. Topology
2. Speed
3. Cost
4. Security
5. Availability
6. Scalability
7. Reliability

Question 18

Characteristics of Networks:

Topology

Answer 18

In networks, there are physical and logical topologies.

The physical topology is the arrangement of cables, network devices, and end systems.

• a physical topology describes how the network devices are actually interconnected with wires and cables

The logical topology is the path over which the data is transferred in a network.

• A logical topology describes how the network devices appear connected to network users.

Question 19

Characteristics of Networks:

Speed:

Answer 19

Speed is a measure of the data rate in bits per second of a given link in the network.

Question 20

Characteristics of Networks:

Cost

Answer 20

Cost indicates the general expense for the

(a) purchasing of network components and the
(b) installation and maintenance of the network.

Question 21

Characteristics of Networks:

Security

Answer 21

Security indicates how protected the network is,

including the information that is transmitted over the network.

Question 22

Characteristics of Networks:

Availability

Answer 22

A measure of the probability that the network will be available for use when it is required.

For networks that are meant to be used 24 hours per day, 7 days per week, 365 days per year,

availability is calculated by dividing the time that it is actually available by the total time in a year and then multiplying by 100 to get a percentage.

Question 23

Name the Formula to Calculate:

Percentage of Network Availability

Answer 23

(Number of minutes in a year – down time) X 100

(number of minutes in a year)

Question 24

Characteristics of Networks:

Scalability

Answer 24

indicates how easily the network can accommodate more users and data transmission requirements.

If you design and optimize a network for only the current requirements, it can be very expensive and difficult to meet new needs when the network grows.

Question 25

# Characteristics of Networks: **Reliability​**

Answer 25

indicates the dependability of the components that make up the network, such as routers, switches, PCs, and servers. Reliability is often measured as a probability of failure or as MTBF\*. \*Mean Time Between Failures

Question 26

# Define **Physical Topology**

Answer 26

the arrangement of cables, network devices, and end systems.

Question 27

# Define **Logical Topology**

Answer 27

the path along which data travels from one point in the network to another

Question 28

# List 4 primary physical topology categories (shapes)

Answer 28

1. Bus 2. Ring 3. Star 4. Mesh

Question 29

# Define **Bus Topology**

Answer 29

Every workstation connected to the main cable. Each workstation directly connected to every other workstation in network. * Early bus topologies cabled endpoint devices using *coaxial cable*. * Modern bus topologies establish bus in hardware device, & connect host devices to bus using *twisted-pair wiring*.

Question 30

# Define **Ring Topology**

Answer 30

Computers and network devices are cabled together so that the last device is connected to the first to form a circle/ring. Each device connected to exactly two neighbors & has no direct connection to a third. * Physical connection made using either coaxial or fiber wiring.

Question 31

# Define **Star Topology**

Answer 31

A central cabling device connects the computers and other network devices. Physical connection commonly made using twisted-pair wiring. * Most common physical topology * This category includes star and extended star topologies. * Star topology is also known as hub-and-spoke topology, due to the shape of the design.

Question 32

# Define **Mesh Topology**

Answer 32

every network device cabled together with many others. * Redundant links increase reliability and self-healing. * Physical connection commonly made using fiber or twisted-pair wiring.

Question 33

# Contrast between **Physical and Logical Topologies**

Answer 33

It is possible the logical and physical topology of a network to be of the same type. However, physical and logical topologies often differ. * Ethernet hub is an example of a physical star topology with a logical bus topology. * Physically hub is star topology; several hosts physically cabled with twisted-pair cables to centralized hub. * Logically, hub is a bus topology; when any host transmits a packet, all devices plugged into hub will receive transmission as if all connected by same single coaxial cable. * Below is a diagram depicting logical topology between 'PC A' and 'Server'. * In this example, packets do not follow shortest physical path * Logical topology requires packets to travel through router in order for two devices to communicate.

Question 34

# Define/ Illustrate/ Interpret **Network Diagram**

Answer 34

*One of most important tasks when designing a network is creating a network diagram.* A map of network, illustrating logical representation of all devices in network and clarifies how they're interconnected. Proper diagram provides information such as interface IDs and network addressing. Other information may be included in network diagram as space allows. * Common to identify interface on a device: * in the S0/0/0 format for a serial interface. * Ethernet interfaces, Fa0/0 identifies Fast Ethernet interface * Gi0/1 identifies Gigabit Ethernet interface. * Also common to include network address of segment in 192.168.1.0/24 format. * 192.168.1.0 indicates the network address, /24 indicates the subnet mask * .1 and .2 at the device ends indicate IP addresses of the interfaces (.1 corresponds to 192.168.1.1).

Question 35

# How does/do . . . **Applications Affect Network Performance**

Answer 35

Different type of applications differ in demands they put on the network. (Increase) in **Demand =** (Decrease) in **Network Performance**

Question 36

# List **3 Types of Applications that Affect Network Performance**

Answer 36

1. ​Batch applications 2. Interactive applications 3. Real-Time applications

Question 37

# Define **Batch Applications**

Answer 37

Applications that send and receive files - Examples of batch applications: * FTP * TFTP - No direct human interaction; once files selected and DL begins, user waits - Bandwidth important but not critical b/c DL completed eventually even w low bandwidth

Question 38

# Define **Interactive Applications**

Answer 38

Applications in which the user waits for a response, e.g. inventory lookup - Human-to-machine interaction - Human waiting for response; response time important more important than batch apps, but not critical, unless waiting becomes excessive

Question 39

# Define **Real-Time Applications**

Answer 39

Voice & video applications that involve human-to-human interaction - Due to amt of info being transmitted, bandwidth is critical - Maximum throughput essential as RTA's do not retransmit lost data - End-to-end latency critical

Question 40

# Define **Latency**

Answer 40

Amount of time for data to travel fom source to destination i.e. speed Affected by: * Physical Distance * Physical elements in channel used to transmit data: * Transmission mediums * Propagation (transmission) * Routers * Storage Delays

Question 41

# Define **Bandwidth**

Answer 41

The maximum amount of data that can travel through a 'channel' - Width of communication band - Not used to measure speed but capacity - High bandwidth =/= high network performance - If throughput affected by latency/packet loss/ jitters, service will see delays despite substantial amt of bandwidth available

Question 42

# Define **Throughput**

Answer 42

Measure rate at which messages arrive at destination successfully - Also measured in (-)b/s - Measuring low throughput indicates probs like packet loss where packets are lost in transit (devastating to VoIP audio calls where audio skips)

Question 43

# Example of: **The Difference Between Bandwidth, Latancy, & Throughput**

Answer 43

**Bandwidth** determines how narrow or wide a pipe is. The narrower it is, the less data is able to be pushed through it at once and vice-versa. **Latency** determines how fast the contents within a pipe can be transferred from the client to the server and back. **Throughput** is the amount of data which can be transferred over a given time period. - Latency affects throughput - Bandwidth does not affect latency and throughput and vice versa