CompTIA A+ Rapid Review: Networking

Objective 2.7: Compare and contrast Internet connection types and features

This objective requires you to know about the different ways that users can connect to the Internet. You should know when the connection types are available or most appropriate. You should also have a basic understanding of the relative speeds of the different connections.

Exam need to know...

• Cable and fiber

  For example: What is the relationship of the speed of cable and fiber broadband connections compared to other connections?

• Phone lines

  For example: What types of connectors are used for phone lines?

• Satellite

  For example: When is satellite Internet access most appropriate?

• Cellular (mobile hotspot)

  For example: What is a MiFi device?

• WiMAX and line of sight wireless Internet service

  For example: Where is WiMAX used?

Cable and fiber

Years ago, all television broadcasts were sent over the air as radio frequency RF transmissions. Anyone that wanted to watch TV used an antenna on their TV or rooftop and had access to a limited number of channels. Telecommunications companies began running cables to as many houses as they could and then charging users to connect to the cable, so most homes now have cable TV. Cable TV provides a clearer picture and delivers more channels, so it quickly became popular.

In time, these telecommunications companies realized that in addition to sending television signals over the cable, they could also provide Internet access over the same cable. These companies expanded their services and became Internet Service Providers (ISPs).

True or false? Broadband cable Internet connections are significantly faster than any dial-up or ISDN access.

Answer: True. Broadband cable has been the fastest Internet connection available to home users for many years.

Cable television originally used copper coaxial cable, and many cable connections still use coaxial cable. However, some telecommunications companies have started to run fiber to neighborhoods and homes as a faster alternative. Fiber cable connections typically provide faster connections than traditional cable TV connections.

Phone lines

In the early days of the Internet, the only way people could connect to the Internet was through the plain old telephone service (POTS). Phone lines are still used to provide Internet access to many people living in rural areas that do not have cable or fiber connections available at their homes.

True or false? Computers with a modem and a POTS line can connect to the Internet.

Answer: True. A dial-up connection to the Internet needs only a computer with a modem and simple phone line.

A modem is a modulator/demodulator that converts the signals between the formats needed by the computer and by the transmission line. The modem can be built into the computer or added as an external device.

The following three different types of connections use phone lines:

• Dial-up connections use a simple POTS phone line and a traditional modem.

• Integrated Services Digital Networks (ISDNs) use digital signals and terminal adapters in place of modems. A benefit is that a user can talk on the phone at the same time that the phone line is being used for the Internet connection.

• Digital subscriber lines (DSLs) also use digital signals and are available in large metropolitan areas. Technically, they use a transceiver instead of a modem, but the transceiver is commonly called a DSL modem.

True or false? In an ADSL line, the upload speed is faster than the download speed.

Answer: False. An asymmetric DSL (ADSL) does have different speeds for uploads and downloads. However, the download speed is faster than the upload speed.

Most users need faster downloads than uploads. For example, when users are browsing the Internet, they typically send very small requests to view a webpage in upload requests. However, the webpage can include a significant amount of data, such as text, graphics, audio, and video that is downloaded to the users.

Satellite

Most rural areas do not have cable television, but they do have satellite television as an alternative. Users can subscribe with a satellite provider. They have satellite dishes that can receive television signals from an orbiting satellite. Additionally, many current satellite television systems can also transmit basic signals up to the satellite.

Just as telecommunications companies began using their cable and fiber connections for Internet access, many satellite providers began using their satellite connections for Internet access. Additionally, some companies specialize in only Internet access via satellite connections.

True or false? A major drawback with satellite signals is signal latency.

Answer: True. Signal latency refers to the amount of delay between when a user sends a request and receives a reply.

With broadband fiber and cable connections, users start to see a webpage download almost immediately when they send the request. In contrast, users with a satellite connection might see a significant delay between the time when they click a link and the webpage starts to load. This is because the signal must travel to the satellite in orbit, back down to Earth, back up to the satellite, and back to the user.

Cellular (mobile hotspot)

Smartphones use cellular access both for telephone calls and for Internet access. When users subscribe to the service, they can surf the Internet and access email with their smartphones. This same service is available for mobile hotspots. A mobile hotspot connects to the cellular service and acts as a wireless router for multiple wireless devices.

True or false? Cellular Internet access is the best choice for a user who frequently travels.

Answer: True. Devices with cellular Internet access can access the Internet from almost anywhere.

Mobile hotspots are also known as MiFi devices. A MiFi device is a small battery-powered device that users can take with them just about anywhere. After turning it on, it automatically connects to the cellular service. Users can configure mobile devices with the MiFi SSID and passphrase and connect to the Internet through the MiFi device. A single MiFi device typically supports five or more wireless devices.

WiMAX and line of sight wireless Internet service

Worldwide Interoperability for Microwave Access (WiMAX) is another wireless standard. It can deliver high-speed wireless Internet access for large geographical areas, such as a metropolitan area network (MAN).

True or false? When connecting to WiMAX networks, WiMAX towers need a clear line of sight between each other.

Answer: True. WiMAX towers use microwave links between each other, and these require a clear line of sight between each other.

Internet service providers (ISPs) have a wired connection to a WiMAX tower. The WiMAX towers connect to each other wirelessly, and end users can connect to the closest tower wirelessly.

Can you answer these questions?

You can find the answers to these questions at the end of this chapter.

1. Which wired Internet connection provides the highest speeds?

2. What type of Internet connections use phone lines?

3. What type of Internet connection is most appropriate for a traveling salesman?

4. What type of Internet connection is mobile and can be used to provide Internet access for multiple users?