Module 2: Network Components, Types, and Connections Flashcards
Explain Network components, types, and connections.
All computers connected to a network that participate directly in network communication are classified as _.
hosts
_ can send and receive messages on the network.
Hosts
In modern networks, computer hosts can act as a _, a _, or both. The software installed on the computer determines which role the computer plays.
client, server
_ are hosts that have software installed which enable them to provide information, like email or web pages, to other hosts on the network.
Servers
Each service requires separate server software. For example, a host requires web server software in order to provide web services to the network. Every destination that you visit online is provided to you by a server located somewhere on a network that is connected to the global internet.
_ are computer hosts that have software installed that enables the hosts to request and display the information obtained from the server.
Clients
An example of client software is a web browser, such as Internet Explorer, Safari, Mozilla Firefox, or Chrome.
Examples of Clients and Servers
* Email - The email server runs email server software. Clients use mail client software, such as Microsoft Outlook, to access email on the server.
* Web - The web server runs web server software. Clients use browser software, such as Windows Internet Explorer, to access web pages on the server.
* File - 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.
Noted
Client and server software usually run on separate computers, but it is also possible for one computer to run both client and server software 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 (P2P) network.
The simplest P2P network consists of two directly connected computers using either a wired or wireless connection. Both computers are then able to use this simple network to exchange data and services with each other, acting as either a client or a server as necessary.
Multiple PCs can also be connected to create a larger P2P network, but this requires a network device, such as a switch, to interconnect the computers.
The main disadvantage of a P2P environment is that the performance of a host can be slowed down if it is acting as both a client and a server at the same time.
In larger businesses, because of the potential for high amounts of network traffic, it is often necessary to have dedicated servers to support the number of service requests.
Noted
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 (P2P) network
The simplest P2P network consists of two directly connected computers using either a _ or _ connection. Both computers are then able to use this simple network to exchange data and services with each other, acting as either a client or a server as necessary.
wired, wireless
Multiple PCs can also be connected to create a larger P2P network, but this requires a _, such as a switch, to interconnect the computers.
network device
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
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
A _ allows a device to act as both a client and a server within the same communication.
P2P application
In this model, every client is a server and every server is a client. P2P applications require that each end device provide a user interface and run a background service.
Some P2P applications use a _ system where resource sharing is decentralized, but the indexes that point to resource locations are stored in a centralized directory. In this system, each peer accesses an index server to get the location of a resource stored on another peer.
hybrid
A computer with _ can provide services simultaneously to one or many clients.
server software
A single computer can run multiple types of server software. In a home or small business, it may be necessary for one computer to act as a file server, a web server, and an email server.
A single computer can also run multiple types of client software. There must be client software for every service required. With multiple clients installed, a host can connect to multiple servers at the same time. For example, a user can check email and view a web page while instant messaging and listening to internet radio.
A computer that has software installed to provide information such as email or web pages to other devices is known as a:
server
A smart phone uses web browser software to request and display a web page. The smart phone is considered what type of computer?
client
A network where two computers are communicating with each other as both a client and as a server is known as a:
peer-to-peer network
Examples of Intermediate Devices
- Router
- Wireless Router
- Switch
- Wireless Access Point
- Call Manager
- Firewall
- Service Provider Switch
- LAN Switch
- Multilayer Switch
Example of End Devices
- Laptop
- Printer
- Smartphone
- IP Phone
- Desktop
- Server
- Wireless Tablet
- Telepresence Endpoint
Examples of Network Media
- LAN Media - used for ISP communications
- WAN Media - used for ISP communications
- Wireless Media
- Cloud - another network or internet
The path that a message takes from its source to destination can be as simple as a single cable connecting one computer to another, or as complex as a network that literally spans the globe. This _ is the platform that supports the network.
network infrastructure
It provides the stable and reliable channel over which our communications can occur.
Network Infrastructure
The network infrastructure contains three categories of hardware components:
- End devices
- Intermediate devices
- Network media
_ and _ are the physical elements, or hardware, of the network.
Devices, media
_ is often the visible components of the network platform such as a laptop, PC, switch, router, wireless access point, or the cabling used to connect the devices.
Hardware
Occasionally, some components may not be so visible. In the case of wireless media, messages are transmitted through the air using invisible _ or _.
radio frequencies, infrared waves
The network devices that people are most familiar with are called _, or hosts. These devices form the interface between users and the underlying communication network.
end devices
Some examples of end devices are as follows:
* Computers (workstations, laptops, file servers, web servers)
* Network printers
* Telephones and teleconferencing equipment
* Security cameras
* Mobile devices (such as smart phones, tablets, PDAs, and wireless debit/credit card readers and barcode scanners)
An _ is either the source or destination of a message transmitted over the network. In order to uniquely identify hosts, addresses are used.
end device (or host)
When a host initiates communication, it uses the _ of the destination host to specify where the message should be sent.
address
Marjani lives on a farm several kilometers outside of Msolwa, Tanzania. Which of the following end devices is she most likely to use to connect to the internet? (Choose two.)
* wireless router
* telepresence endpoint
* network printer
* smartphone
* wireless tablet
smartphone
wireless tablet
Eilert recently got a job with a computer support services company in his hometown of Falun, Sweden. A customer has asked for someone to come connect their home network to the internet. They only have a cable modem. Which of the following intermediary devices would Eilert most likely take with him to the job?
* desktop computer
* wireless router
* firewall appliance
* multilayer switch
* LAN switch
wireless router
Rosalía works as a community health worker in Rio Claro, Brazil. Most of her time is spent making home visits to provide primary care to people in her community. However, she requires internet access to maintain her patient records and provide videoconferencing with a doctor, when needed. What end device and media type does Rosalía most likely use? (Choose two.)
* LAN media
* wireless media
* WAN media
* desktop computer
* tablet
* router
wireless media, tablet
An _ provides the link between the home network and the internet.
Internet Service Provider (ISP)
An ISP can be the local cable provider, a landline telephone service provider, the cellular network that provides your smartphone service, or an independent provider who leases bandwidth on the physical network infrastructure of another company.
Many ISPs also offer additional services to their contract subscribers. These services can include email accounts, network storage, and website hosting and automated backup or security services.
ISPs are critical to communications across the global internet. Each ISP connects to other ISPs to form a network of links that interconnect users all over the world. ISPs are connected in a hierarchical manner that ensures that internet traffic generally takes the shortest path from the source to the destination.
Noted
The internet backbone is like an information super highway that provides high-speed data links to connect the various service provider networks in major metropolitan areas around the world. The primary medium that connects the internet backbone is _ cable. This cable is typically installed underground to connect cities within continents.
fiber-optic
Fiber-optic cables also run under the sea to connect continents, countries, and cities.
ISP Connections
The interconnection of ISPs that forms the backbone of the internet is a complex web of fiber-optic cables with expensive networking switches and routers that direct the flow of information between source and destination hosts. Average home users are not aware of the infrastructure outside of their network. For a home user, connecting to the ISP is a fairly uncomplicated process.
The top portion of the figure displays the simplest ISP connection option. It consists of a modem that provides a direct connection between a computer and the ISP. This option should not be used though, because your computer is not protected on the internet.
As shown in the bottom portion of the figure, a router is required to securely connect a computer to an ISP. This is the most common connection option. It consists of using a wireless integrated router to connect to the ISP. The router includes a switch to connect wired hosts and a wireless AP to connect wireless hosts. The router also provides client IP addressing information and security for inside hosts.
2.3.3 Cable and DSL Connections
Most home network users do not connect to their service providers with fiber-optic cables. The figure illustrates common connection options for small office and home users. The two most common methods are as follows:
Cable - Typically offered by cable television service providers, the internet data signal is carried on the same coaxial cable that delivers cable television. It provides a high bandwidth, always on, connection to the internet. A special cable modem separates the internet data signal from the other signals carried on the cable and provides an Ethernet connection to a host computer or LAN.
DSL - Digital Subscriber Line provides a high bandwidth, always on, connection to the internet. It requires a special high-speed modem that separates the DSL signal from the telephone signal and provides an Ethernet connection to a host computer or LAN. DSL runs over a telephone line, with the line split into three channels. One channel is used for voice telephone calls. This channel allows an individual to receive phone calls without disconnecting from the internet. A second channel is a faster download channel, used to receive information from the internet. The third channel is used for sending or uploading information. This channel is usually slightly slower than the download channel. The quality and speed of the DSL connection depends mainly on the quality of the phone line and the distance from the central office of your phone company The farther you are from the central office, the slower the connection.
Noted
2.3.4 Additional Connectivity Options
Other ISP connection options for home users include the following:
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 will be limited by the capabilities of the phone and the cell tower to which it is connected. The availability of cellular internet access is a real benefit for people in areas that would otherwise have no internet connectivity at all, or for people who are constantly on the move. The downside of cellular connectivity is that the carrier usually meters the bandwidth usage of the connection and may charge extra for bandwidth that exceeds the contract data plan.
Satellite
Satellite service is a good option for homes or offices that do not have access to DSL or cable. Satellite dishes (see figure) require a clear line of sight to the satellite and so might be difficult in heavily wooded areas or places with other overhead obstructions. Speeds will vary depending on the contract, though they are generally good. Equipment and installation costs can be high (although check the provider for special deals), with a moderate monthly fee thereafter. Like cellular access, the availability of satellite internet access is a real benefit in areas that would otherwise have no internet connectivity at all.
Dial-up Telephone
An inexpensive option that uses any phone line and a modem. To connect to the ISP, a user calls the ISP access phone number. The low bandwidth provided by a dial-up modem connection is usually not sufficient for large data transfer, although it is useful for mobile access while traveling. A modem dial-up connection should only be considered when higher speed connection options are not available.
Noted
In metropolitan areas, many apartments and small offices are being connected directly with _ cables. This enables an internet service provider to provide higher bandwidth speeds and support more services such as internet, phone, and TV.
fiber-optic
The choice of connection varies depending on geographical location and service provider availability.
What is a service that provides an internet data signal on the same network that delivers broadcast television and phone service?
* Cable internet
* Guest access
* Cellular data plan
* Digital Subscriber Line (DSL)
Cable internet
What is a service that provides high bandwidth, always on, connection using existing land-line telephone wires?
* Cellular data plan
* Guest access
* Digital Subscriber Line (DSL)
* Cable internet
Digital Subscriber Line (DSL)
What is an internet service that uses mobile phone networks to transmit data?
* Digital Subscriber Line (DSL)
* Cellular data plan
* Guest access
* Cable internet
Cellular data plan
2.4.1 What Did I Learn in this Module?
Clients and Servers
All computers connected to a network that participate directly in network communication are classified as hosts. Hosts can send and receive messages on the network. In modern networks, computer hosts can act as a client, a server, or both. The software installed on the computer determines which role the computer plays.
Client and server software usually run on separate computers, but it is also possible for one computer to run both client and server software 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 P2P network. In larger businesses, because of the potential for high amounts of network traffic, it is often necessary to have dedicated servers to support the number of service requests. P2P networks are easy to set up, less complex, lower in cost, and can be used for simple tasks such as transferring files and sharing printers. However, there is no centralized administration. They have less security, are not scalable, and can perform slower.
Noted
2.4.1 What Did I Learn in this Module?
Network Components
There are symbols that represent various types of networking equipment. The network infrastructure is the platform that supports the network. It provides the stable and reliable channel over which our communications can occur. The network infrastructure contains three categories of hardware components: end devices, intermediate devices, and network media. Hardware is often the visible components of the network platform such as a laptop, PC, switch, router, wireless access point, or the cabling used to connect the devices. Components that are not visible include wireless media.
End devices, or hosts, form the interface between users and the underlying communication network. Some examples of end devices include:
* Computers (workstations, laptops, file servers, web servers)
* Network printers
* Telephones and teleconferencing equipment
* Security cameras
* Mobile devices (such as smartphones, tablets, PDAs, and wireless debit/credit card readers and barcode scanners)
Noted
2.4.1 What Did I Learn in this Module?
ISP Connectivity Options
An ISP provides the link between the home network and the internet. An ISP can be the local cable provider, a landline telephone service provider, the cellular network that provides your smartphone service, or an independent provider who leases bandwidth on the physical network infrastructure of another company. Each ISP connects to other ISPs to form a network of links that interconnect users all over the world. ISPs are connected in a hierarchical manner that ensures that internet traffic generally takes the shortest path from the source to the destination.
The interconnection of ISPs that forms the backbone of the internet is a complex web of fiber-optic cables with expensive networking switches and routers that direct the flow of information between source and destination hosts.
For a home user, connecting to the ISP is a fairly uncomplicated process. This is the most common connection option. It consists of using a wireless integrated router to connect to the ISP. The router includes a switch to connect wired hosts and a wireless AP to connect wireless hosts. The router also provides client IP addressing information and security for inside hosts. The two most common methods are cable and DSL. Other options include cellular, satellite, and dial-up telephone.
Noted
