Modules 1 - 3: Basic Network Connectivity and Communications

Question 1

What is a Host in the network?

Answer 1

computers that are connected to a network and participate directly in network communication are classified as hosts. Hosts can be called end devices. Some hosts are also called clients.

Question 2

How host are identified?

Answer 2

hosts specifically refers to devices on the network that are assigned a number for communication purposes. This number identifies the host within a particular network. This number is called the Internet Protocol (IP) address. An IP address identifies the host and the network to which the host is attached.

Question 3

What is a server?

Answer 3

Servers are computers with software that allow them to provide information, like email or web pages, to other end devices on the network. Each service requires separate server software. For example, a server requires web server software in order to provide web services to the network. A computer with server software can provide services simultaneously to many different clients.

Question 4

what is client software?

Answer 4

Clients are a type of host. Clients have software for requesting and displaying the information obtained from the server
An example of client software is a web browser, like Chrome or Firefox. A single computer can also run multiple types of client software. For example, a user can check email and view a web page while instant messaging and listening to an audio stream.

Question 5

what are the common types of servers?

Answer 5

Email, Web, File

Question 6

what is an Email server?

Answer 6

The email server runs email server software. Clients use mail client software, such as Microsoft Outlook, to access email on the server.

Question 7

what is a Web server?

Answer 7

The web server runs web server software. Clients use browser software, such as Windows Internet Explorer, to access web pages on the server.

Question 8

What is a File server?

Answer 8

The file server stores corporate and user files in a central location. The client devices access these files with client software such as the Windows File Explorer.

Question 9

What is a Peer-to-peer network?

Answer 9

Client and server software usually run on separate computers, but it is also possible for one computer to be used for both roles at the same time. In small businesses and homes, many computers function as the servers and clients on the network. This type of network is called a peer-to-peer networ

Question 10

Expand USB

Answer 10

Universal Serial Bus

Question 11

Expand NIC

Answer 11

network interface card

Question 12

Advantage of Peer-to-Peer networking

Answer 12

The advantages of peer-to-peer networking:

> Easy to set up
Less complex
Lower cost because network devices and dedicated servers may not be required
Can be used for simple tasks such as transferring files and sharing printers

Question 13

disadvantages of peer-to-peer networking

Answer 13

The disadvantages of peer-to-peer networking:

> No centralized administration
Not as secure
Not scalable
All devices may act as both clients and servers which can slow their performance

Question 14

What are End Devices

Answer 14

An end device is either the source or destination of a message transmitted over the network.

Question 15

What are Intermediary Devices

Answer 15

Intermediary devices connect the individual end devices to the network. They can connect multiple individual networks to form an internetwork. These intermediary devices provide connectivity and ensure that data flows across the network

Question 16

How Intermediary Devices works

Answer 16

Intermediary devices use the destination end device address, in conjunction with information about the network interconnections, to determine the path that messages should take through the network. Examples of the more common intermediary devices are Routers, LAN Switch, Multilayer Switch, Firewall Appliance

Question 17

Functions of Intermediate devices

Answer 17

Intermediary network devices perform some or all of these functions:

> Regenerate and retransmit communication signals

> Maintain information about what pathways exist
through the network and internetwork

> Notify other devices of errors and communication
failures

> Direct data along alternate pathways when there is a
link failure

> Classify and direct messages according to priorities

> Permit or deny the flow of data, based on security
settings

Note: Not shown is a legacy Ethernet hub. An Ethernet hub is also known as a multiport repeater. Repeaters regenerate and retransmit communication signals. Notice that all intermediary devices perform the function of a repeater.

Question 18

What is a Network Media

Answer 18

The communication transmits across a network on media. The media provides the channel over which the message travels from source to destination.

Question 19

Types of a Network Media

Answer 19

Modern networks primarily use three types of media to interconnect devices, as shown in the figure:

> Metal wires within cables - Data is encoded into
electrical impulses.

> Glass or plastic fibers within cables (fiber-optic cable) -
Data is encoded into pulses of light.

> Wireless transmission - Data is encoded via modulation
of specific frequencies of electromagnetic waves.

Question 20

1. Which of the following is the name for all computers connected to a network that participate directly in network communication?
2. When data is encoded as pulses of light, which media is being used to transmit the data?

3. Which two devices are intermediary devices? (Choose two)
>hosts
>Routers
>switches
>servers

Answer 20

1. Hosts
2. Fibre optics cable
3. Routers, Switches

Question 21

What is a topology diagram?

Answer 21

A diagram provides an easy way to understand how devices connect in a large network. This type of “picture” of a network is known as a topology diagram

Topology diagrams are mandatory documentation for anyone working with a network. They provide a visual map of how the network is connected.

Question 22

What is NIC

Answer 22

A NIC physically connects the end device to the network

Question 23

What is a Physical Port

Answer 23

A connector or outlet on a networking device where the media connects to an end device or another networking device.

Question 24

What is a Network Interface

Answer 24

Specialized ports on a networking device that connect to individual networks. Because routers connect networks, the ports on a router are referred to as network interfaces.

Question 25

Types of topology diagrams

Answer 25

Physical Topology Diagrams Physical topology diagrams illustrate the physical location of intermediary devices and cable installation. You can see that the rooms in which these devices are located are labeled in this physical topology. Logical Topology Diagrams Logical topology diagrams illustrate devices, ports, and the addressing scheme of the network. You can see which end devices are connected to which intermediary devices and what media is being used.

Question 26

1. Which connection physically connects the end device to the network? 2. Which connections are specialized ports on a networking device that connect to individual networks? 3. Which type of network topology lets you see which end devices are connected to which intermediary devices and what media is being used? 4. Which type of network topology lets you see the actual location of intermediary devices and cable installation?

Answer 26

1. NIC 2. network interface 3. logical topology 4. physical topology

Question 27

what are the most common types of network infrastructures?

Answer 27

Local Area Networks (LANs), and Wide Area Networks (WANs)

Question 28

what is LAN

Answer 28

A LAN is a network infrastructure that spans a small geographical area. LANs have specific characteristics: > LANs interconnect end devices in a limited area such as a home, school, office building, or campus. > A LAN is usually administered by a single organization or individual. Administrative control is enforced at the network level and governs the security and access control policies. > LANs provide high-speed bandwidth to internal end devices and intermediary devices

Question 29

what is WAN

Answer 29

WAN which interconnects two LANs. A WAN is a network infrastructure that spans a wide geographical area. WANs are typically managed by service providers (SPs) or Internet Service Providers (ISPs). WANs have specific characteristics: > WANs interconnect LANs over wide geographical areas such as between cities, states, provinces, countries, or continents. > WANs are usually administered by multiple service providers. > WANs typically provide slower speed links between LANs.

Question 30

What is internet

Answer 30

The internet is a worldwide collection of interconnected networks

Question 31

internet facts

Answer 31

The internet is not owned by any individual or group. Ensuring effective communication across this diverse infrastructure requires the application of consistent and commonly recognized technologies and standards as well as the cooperation of many network administration agencies. There are organizations that were developed to help maintain the structure and standardization of internet protocols and processes. These organizations include the Internet Engineering Task Force (IETF), Internet Corporation for Assigned Names and Numbers (ICANN), and the Internet Architecture Board (IAB), plus many others.

Question 32

terms of the internet are

Answer 32

There are two other terms that are similar to the term internet: intranet and extranet.

Question 33

intranet

Answer 33

Intranet is a term often used to refer to a private connection of LANs and WANs that belongs to an organization. An intranet is designed to be accessible only by the organization's members, employees, or others with authorization.

Question 34

extranet

Answer 34

An organization may use an extranet to provide secure and safe access to individuals who work for a different organization but require access to the organization’s data. Here are some examples of extranets: A company that is providing access to outside suppliers and contractors A hospital that is providing a booking system to doctors so they can make appointments for their patients A local office of education that is providing budget and personnel information to the schools in its district

Question 35

1. Which network infrastructure provides access to users and end devices in a small geographical area, which is typically a network in a department in an enterprise, a home, or a small business? 2. Which network infrastructure might an organization use to provide secure and safe access to individuals who work for a different organization but require access to the organization’s data? 3. Which network infrastructure provides access to other networks over a large geographical area, which is often owned and managed by a telecommunications service provider?

Answer 35

1. LAN 2. Extranet 3. WAN

Question 36

expand (DSL)

Answer 36

digital subscriber line

Question 37

expand ISP

Answer 37

Internet service provider

Question 38

``` Home and Small Office Internet Connections: what is a > cable > DSL > cellular > satellite > Dial-up telephone ```

Answer 38

Cable - Typically offered by cable television service providers, the internet data signal transmits on the same cable that delivers cable television. It provides a high bandwidth, high availability, and an always-on connection to the internet. DSL - Digital Subscriber Lines also provide high bandwidth, high availability, and an always-on connection to the internet. DSL runs over a telephone line. In general, small office and home office users connect using Asymmetrical DSL (ADSL), which means that the download speed is faster than the upload speed. Cellular - Cellular internet access uses a cell phone network to connect. Wherever you can get a cellular signal, you can get cellular internet access. Performance is limited by the capabilities of the phone and the cell tower to which it is connected. Satellite - The availability of satellite internet access is a benefit in those areas that would otherwise have no internet connectivity at all. Satellite dishes require a clear line of sight to the satellite. Dial-up Telephone - An inexpensive option that uses any phone line and a modem. The low bandwidth provided by a dial-up modem connection is not sufficient for large data transfer, although it is useful for mobile access while traveling.

Question 39

``` Businesses Internet Connections: what is a > cable > Dedicated Leased Line > Metro Ethernet > Business DSL > satellite ```

Answer 39

Dedicated Leased Line - Leased lines are reserved circuits within the service provider’s network that connect geographically separated offices for private voice and/or data networking. The circuits are rented at a monthly or yearly rate. Metro Ethernet - This is sometimes known as Ethernet WAN. In this module, we will refer to it as Metro Ethernet. Metro ethernets extend LAN access technology into the WAN. Ethernet is a LAN technology you will learn about in a later module. Business DSL - Business DSL is available in various formats. A popular choice is Symmetric Digital Subscriber Line (SDSL) which is similar to the consumer version of DSL but provides uploads and downloads at the same high speeds. Satellite - Satellite service can provide a connection when a wired solution is not available.

Question 40

what is a Converged Networks

Answer 40

Converged networks are capable of delivering data, voice, and video between many different types of devices over the same network infrastructure. Converged data networks carry multiple services on one network.

Question 41

characteristics that network architects

Answer 41

> Fault Tolerance > Scalability > Quality of Service (QoS) > Security

Question 42

what is Fault Tolerance

Answer 42

A fault-tolerant network is one that limits the number of affected devices during a failure. It is built to allow quick recovery when such a failure occurs. These networks depend on multiple paths between the source and destination of a message. If one path fails, the messages are instantly sent over a different link. Having multiple paths to a destination is known as redundancy.

Question 43

what is a packet

Answer 43

A single message, such as an email or a video stream, is broken into multiple message blocks, called packets. Each packet has the necessary addressing information of the source and destination of the message. The routers within the network switch the packets based on the condition of the network at that moment.

Question 44

what is Scalability

Answer 44

A scalable network expands quickly to support new users and applications. It does this without degrading the performance of services that are being accessed by existing users.

Question 45

what is Quality of Service

Answer 45

Quality of Service (QoS) is an increasing requirement of networks today. New applications available to users over networks, such as voice and live video transmissions, create higher expectations for the quality of the delivered services. QoS becomes a primary mechanism for managing congestion and ensuring reliable delivery of content to all users. Congestion occurs when the demand for bandwidth exceeds the amount available. When simultaneous communications are attempted across the network, the demand for network bandwidth can exceed its availability, creating network congestion. The focus of QoS is to prioritize time-sensitive traffic. The type of traffic, not the content of the traffic, is what is important.

Question 46

types of network security

Answer 46

network infrastructure security and information security.

Question 47

1. When designers follow accepted standards and protocols, which of the four basic characteristics of network architecture is achieved? 2. Confidentiality, integrity, and availability are requirements of which of the four basic characteristics of network architecture? 3. With which type of policy, a router can manage the flow of data and voice traffic, giving priority to voice communications if the network experiences congestion? 4. Having multiple paths to a destination is known as redundancy. This is an example of which characteristic of network architecture?

Answer 47

1. scalability 2. security 3. Qos 4. fault tolerance

Question 48

Cloud Computing

Answer 48

Cloud computing is one of the ways that we access and store data. Cloud computing allows us to store personal files, even back up an entire drive on servers over the internet. Applications such as word processing and photo editing can be accessed using the cloud.

Question 49

Cloud Types

Answer 49

Public Cloud - Cloud-based applications and services offered in a public cloud are made available to the general population. Services may be free or are offered on a pay-per-use model, such as paying for online storage. The public cloud uses the internet to provide services. Private Cloud - Cloud-based applications and services offered in a private cloud are intended for a specific organization or entity, such as a government. A private cloud can be set up using the organization’s private network, though this can be expensive to build and maintain. A private cloud can also be managed by an outside organization with strict access security. Hybrid clouds - A hybrid cloud is made up of two or more clouds (example: part private, part public), where each part remains a distinct object, but both are connected using a single architecture. Individuals on a hybrid cloud would be able to have degrees of access to various services based on user access rights. Community clouds - A community cloud is created for exclusive use by specific entities or organizations. The differences between public clouds and community clouds are the functional needs that have been customized for the community. For example, healthcare organizations must remain compliant with policies and laws (e.g., HIPAA) that require special authentication and confidentiality. Community clouds are used by multiple organizations that have similar needs and concerns. Community clouds are similar to a public cloud environment, but with set levels of security, privacy, and even regulatory compliance of a private cloud

Question 50

what is a Powerline Networking

Answer 50

Powerline networking for home networks uses existing electrical wiring to connect devices

Question 51

expand WISP

Answer 51

Wireless Internet Service Provider

Question 52

what is WISP

Answer 52

an ISP that connects subscribers to a designated access point or hot spot using similar wireless technologies found in-home wireless local area networks (WLANs). WISPs are more commonly found in rural environments where DSL or cable services are not available.

Question 53

common external threats to networks

Answer 53

Viruses, worms, and Trojan horses - These contain malicious software or code running on a user device. Spyware and adware - These are types of software that are installed on a user’s device. The software then secretly collects information about the user. Zero-day attacks - Also called zero-hour attacks, these occur on the first day that a vulnerability becomes known. Threat actor attacks - A malicious person attacks user devices or network resources. Denial of service attacks - These attacks slow or crash applications and processes on a network device. Data interception and theft - This attack captures private information from an organization’s network. Identity theft - This attack steals the login credentials of a user in order to access private data.

Question 54

basic security components for a home

Answer 54

Antivirus and antispyware - These applications help to protect end devices from becoming infected with malicious software. Firewall filtering - Firewall filtering blocks unauthorized access into and out of the network. This may include a host-based firewall system that prevents unauthorized access to the end device, or a basic filtering service on the home router to prevent unauthorized access from the outside world into the network.

Question 55

Larger networks and corporate networks security requirements:

Answer 55

Dedicated firewall systems - These provide more advanced firewall capabilities that can filter large amounts of traffic with more granularity. Access control lists (ACL) - These further filter access and traffic forwarding based on IP addresses and applications. Intrusion prevention systems (IPS) - These identify fast-spreading threats, such as zero-day or zero-hour attacks. Virtual private networks (VPN) - These provide secure access into an organization for remote workers.