2.3 Protocols for wireless networking Flashcards
Compare and contrast protocols for wireless networking
The network specialist sets up a long-range fixed wireless installation and operates on a public frequency without a license. Is this legal?
-No. The public spectrum requires the operator using that frequency band to have a license to operate.
-No. The point-to-point fixed wireless uses ground-based high-gain microwave antennas precisely aligned with one another, requiring a license.
-Yes. Installations may use an unlicensed spectrum but cannot exceed the Effective Isotropic Radiated Power (EIRP) defined from regulations.
-Yes. However, the radio spectrum requires the operator to carefully shield the transmitters covering long distances to avoid obtaining a license.
Yes. Installations may use an unlicensed spectrum but cannot exceed the Effective Isotropic Radiated Power (EIRP) defined from regulations.
*Installations may use any unlicensed public spectrum but must not exceed the band’s effective isotropic radiated power (EIRP) defined by regulations.
~Regulation of the radio spectrum means that transmitters covering long distances must be carefully configured not to accept EIRP and do not need a license unless looking to have exclusive rights of a frequency band of a given area from the FCC, which means licensed.
~Point-to-point line of sight fixed wireless using ground-based high-gain microwave antennas precisely aligned with one another do not need a license to operate.
~Unlicensed spectrum means the operator uses a public frequency anyone can use. The regulatory requirements will limit the power output, such as EIRP decibels isotropic (dBi), to minimize potential conflicts.
Suppose a network specialist establishes a fixed long-range wireless device to configure a bridge between two networks and wants to use a specific frequency. What would be the best way for the operator to ensure signal quality?
-Install antennas to transmit signals via satellite unobstructed from single directions not needing a license.
-Obtain a license to purchase exclusive rights to the frequency within a geographical area from the FCC.
-Use a frequency not needing a license and minimize conflicts by ensuring the power output is strong.
-Use a public unlicensed frequency but understand that these frequencies mean interferences are a risk.
Obtain a license to purchase exclusive rights to the frequency within a geographical area from the FCC.
*Regulations state that to cover long distances, the operator must carefully configure devices with precisely aligned point-to-point line of sight, fixed wireless ground-based high-gain microwaves, and a license for exclusive rights to a frequency given by the Federal Communications Commission (FCC).
~Unlicensed frequency spectrum means the operator uses a public frequency anyone can use, and interference is high risk and unregulated.
~Regulatory requirements limit power outputs to minimize the risk of interference and the potential for conflicts.
~The antennas themselves are typically affixed to the top of tall buildings or mounted on tall poles to reduce the risk of obstructions. If antennas are precisely aligned needing a long-range fixed wireless connection, they must be licensed.
A systems engineer is trying to identify suitable smartphone models to issue to field sales staff. The models must be able to use digital payments. What type of sensor must the devices have?
-Indoor positioning system (IPS)
-Bluetooth
-Radio-frequency identification system (RFID)
-Near-field communication system (NFC)
Near-field Communication system (NFC)
*Near-field communication (NFC) allows the user to touch the phone to a point-of-sale terminal to authorize payment in conjunction with a wallet app.
~A radio-frequency ID (RFID) identifies and tracks objects using specially encoded tags. The tags can be unpowered and passive, or powered and active, but not used in digital payments.
~An indoor positioning system (IPS) shows a device’s location by triangulating its proximity to other radio sources, such as a cellular radio tower’s Wi-Fi access points, and does not involve digital payments.
~Bluetooth connects peripheral devices to PCs and mobiles and shares data between two systems, such as radios, speakers, and wearable technology. It is not involved in digital payments.
Which system works out a device’s location by triangulating its proximity to other radio sources through identifying and tracking objects using special tags?
-Near-field communication system (NFC)
-Indoor positioning system (IPS)
-Radio-frequency identification system (RFID)
-Global Positioning System (GPS)
Radio-frequency identification system (RFID)
*Radio-frequency ID (RFID) identifies and tracks objects using specially encoded tags that can be unpowered and passive, responding when scanned at close range or from a powered, active device within 100 m.
~Global Positioning System (GPS) determines a device’s latitude and longitude based on information received from orbital satellites via a GPS sensor and does not use special tags.
~Near-field communication (NFC) is a peer-to-peer version of RFID. The device can work as both tag and reader to exchange information with other NFC devices, like digital payments.
~An indoor positioning system (IPS) determines a device’s location by triangulating its proximity to other radio sources, such as cellular radio towers, Wi-Fi access points, and Bluetooth/RFID beacons without special tags.
Which of the following is a device that works as both tag and reader, exchanges information with other like devices, and is mainly used for payment readers and security tags, although increasingly used in mobile devices for point of sale (POS) connections?
-An RFID tag
-A long-range wireless adapter
-An NFC chip
-A Bluetooth link
An NFC chip
*A near-field communication (NFC) chip is a peer-to-peer (P2P) version of RFID, works as a tag and reader, allows users’ phones as a point-of-sale (POS) terminal with a wallet app, and is progressively found built into mobile devices.
~Radio-frequency ID (RFID) is a means of identifying and tracking objects using specially encoded tags. When an RFID reader scans a tag, the tag responds with the information programmed into it.
~Bluetooth connects peripheral devices to PCs and mobile devices, such as smartphones, tablets, wearable technology, audio speakers, and headphones.
~A long-range fixed wireless adapter is a technology used to configure a bridge between two networks.
Wi-Fi 5 is designed to work in which band(s)?
-Both 2.4 and 5 GHz
-Neither 2.4 nor 5 GHz
-2.4 GHZ
-5GHZ
5GHz
*Wi-Fi 5 works only in the 5 GHz band. So while it can support 2.4 GHz, it needs a dual-band adapter to work with 2.4 GHz.
~Wi-Fi 5 can use a dual-band access point radio to support clients on 2.4 GHz or legacy standards (802.11g/n) but works only in the 5 GHz band.
~A tri-band access point has one 2.4 GHz radio and two 5 GHz radios. Wi-Fi 5 will allow up to eight streams, though in practice, most Wi-Fi 5 access points only support 4x4 streams.
~Wi-Fi 5 works only in the 5 GHz band but can support 2.4 GHz if necessary.
Some products are known to use the combined throughput of all radios. For example, the AX6000 claims nominal rates of 1,148 Mbps on the 2.4 GHz radio and 4,804 Mbps over 5 GHz. This type is an example of what?
-A device for Wi-Fi 6 that can operate on both bands
-A Wi-Fi 5 adapter that can operate on both bands
-A WPA 2 connection of WPA3 device
-An upgraded Wi-Fi 4 set to operate on both bands
A device for Wi-Fi 6 that can operate on both bands
*A 2.4 GHz band allows legacy connections with WPA2-Personal security, while the 5 GHz network is for 802.11ax or Wi-Fi 6-capable devices using WPA3-SAE authentication.
~Wi-Fi 5 works only in the 5 GHz band. A dual-band access point can use its 2.4 GHz radio to support clients on legacy standards (802.11g/n) but is an unusual connection.
~The legacy standard 802.11n is now officially designated as Wi-Fi 4. There have been improvements to keep it viable, but it cannot operate on both bands.
~WPA2 uses a 4-way handshake to allow an access point, authentication, and data encryption; however, neither WEP nor WPA are secure enough for continued use.
What is the difference between licensed and unlicensed when using wireless technology to configure a bridge between two networks? (Select all that apply.)
-Unlicensed means the operator uses a public frequency that anyone can use.
-Licensed means the operator purchased exclusive rights to a band in a given location.
-Unlicensed means power focuses in a single direction over a wider area.
-Licensed means the power output of a device gets boosted by directionality.
Unlicensed means the operator uses a public frequency that anyone can use & Licensed means the operator purchased exclusive rights to a band in a given location.
*Licensed means that the network operator purchases the exclusive right to use a frequency band within a given geographical area from the regulator.
*An unlicensed spectrum means the operator uses a public frequency band, such as 900 MHz, 2.4 GHz, and 5 GHz. Anyone can use these frequencies; however, interference is a risk.
~Antenna gain is the amount of an unlicensed signal boosted by directionality. It focuses in a single direction rather than over a wide area, not the device’s power output.
~Regulatory requirements in unlicensed devices limit power output.
Unlicensed spectrum refers to the operator using a public frequency band, such as 900 MHz or which band(s)?
-5 GHZ only
-2.4 GHZ only
-Both 2.4 and 5 GHz
-20 MHz channels on 2.4 GHz
Both 2.4 and 5GHZ
*An unlicensed spectrum means the operator can use a public frequency band like 900 MHz, both 2.4 GHz and 5 GHz, as long-range fixed wireless.
~An unlicensed spectrum means the operator can use a public frequency band, meaning both 2.4 GHz and 5 GHz but are open to interference risks.
~The Unlicensed National Information Infrastructure (U-NII) sub-bands form the 20 MHz channels used in the 5 GHz frequency band.
~Unlicensed public frequency bands can use either 2.4 or 5 GHz and are open for anyone to use but are open to interference risks.
A network administrator is assessing standards compatibility for a Wi-Fi network. Most employees have mobile devices with single-band 2.4 GHz radios. Which Wi-Fi standards work in this band? (Select all that apply.)
-Wi-Fi 4 (802.11n)
-Wi-Fi 6 (802.11ax)
-Wi-Fi 5 (802.11ac)
-IEEE standard 802.11a
Wi-Fi 4 (802.11n) and Wi-Fi 6 (802.11ax)
*Wi-Fi 6 works in both the 2.4 GHz and 5 GHz bands, but the 5 GHz standard is less effective at penetrating solid surfaces and does not support the maximum ranges achieved with 2.4 GHz standards.
*Substantial improvements have occurred with Wi-Fi 4 since 2009, and now 802.11n is officially designated as Wi-Fi 4 and works in the 2.4 GHz band.
~The IEEE 802.11a standard uses the 5 GHz frequency band only. Most mobile devices use a single-band 2.4 GHz radio.
~Wi-Fi 5 (802.11ac) works only at 5 GHz. Standard 802.11b/g/n are the legacy standards for Wi-Fi 6 and Wi-Fi- 4.
During a meeting, the network supervisor argued that they should use a 5 GHz band in their new open-plan office setting, but the owner heard that the 2.4 GHz band is the one to use since it has a shorter range. Who is right and why? (Select all that apply.)
-The supervisor is correct. A 5 GHz band power’s regulations and DFS prevents signals from interfering.
-The owner is correct. Despite the open floor plan, a 5 GHz has a shorter range.
-
The owner is correct. The chances of interference are higher on a 5 GHz band.
-The supervisor is correct. A 2.4 GHz network does not have enough space for separate networks.
The supervisor is correct. A 5 GHz band power’s regulations and DFS prevents signals from interfering & The supervisor is correct. A 2.4 GHz network does not have enough space for separate networks.
*In a 2.4 GHz network, each channel is only 5 MHz wide. Wi-Fi requires 20 MHz. The 5 GHz band is subdivided into 23 non-overlapping channels, each 20 MHz wide, reducing the risk of interference.
*In a 2.4 GHz band, there is no room for separate networks. Therefore, the chances of overlap/interference are high using the 2.4 GHz band products.
~There are regulatory limits on power output constraining ranges of Wi-Fi devices. The 5 GHz band must use DFS to prevent Wi-Fi signals from interfering with radar/satellite signals.
~An open plan does not have solid walls or building features to block signals. The slightly reduced range of 5 GHz (not 2.4 GHz) should not be a significant drawback.
Which of the following devices uses an applet in the Control Panel or Windows Settings, pairs with other devices to work, and puts an icon in the notification area of the paired device?
-Bluetooth
-A low-energy RFC
-An NFC tag
-An RFID tag
Bluetooth
*Bluetooth technology works best at the 2.4 GHz band, is portable, although some desktop systems are beginning to use it, and is usually wearable.
~A radio-frequency ID (RFID) tag identifies and tracks objects using encoded tags, such as point-of-sale card readers, stickers, labels, and other equipment. RFIDs are not usually portable or wearable.
~A near-field communication (NFC) is a peer-to-peer version of RFID and works as a tag and reader, exchanging information with other NFC devices. NFCs typically work up to 2 inches and are not wearable but beginning to be found in smartphones.
~Request for Comments (RFCs) is not a device. Instead, RFCs are an official repository for published standards, usually referring to the IPv4 address scheme (RFC 1918).
The network operator is trying to minimize the potential for conflicts in an unlicensed power output but knows regulatory requirements limit them. Gain measures a wireless signal’s power. What is gain, and how is it measured?
-Gain is the sum of transmit power expressed in dBm.
-Gain is the transmit strength of the radio measured in dBm.
-Gain is the wireless antenna frequency working over long-range bands, measured in dBi.
-Gain is the amount of boost that occurs in a focused antenna signal, measured in dBi.
Gain is the amount of boost that occurs in a focused antenna signal, measured in dBi.
*Gain is the amount of boost an antenna signal receives by directionality, focusing the signal in a single direction rather than spreading it over a wide area, and is measured in decibels isotropic (dBi).
~Effective isotropic radiated power (EIRP) is the sum of transmit power and gain, expressed in decibel per milliwatt (dBm).
~Transmit power is the basic strength of the radio, measured in decibel per milliwatt (dBm).
~Point-to-point wireless antenna frequencies working over longer ranges are not gain. Gain is the amount of boost an antenna signal receives by directionality and is measured in decibels isotropic (dBi).
The standards compatibility for a Wi-Fi network that will also be supporting most employees with mobile devices plans to use 802.11b/g/n to support its clients. Which GHz band is the best to use to support clients? (Select all that apply.)
-Wi-Fi 6 to work with the 2.4 GHz band
-Wi-Fi 4 working with the 5 GHz band
-Wi-Fi 6 working with dual band adapter using both the 2.4 ad 5 GHz bands
-Wi-Fi 5 working with the 5 GHz band
Wi-Fi 6 to work with 2.4 GHz band & Wi-Fi 6 working with dual band adapter using both 2.4 and 5 GHz bands
*Most mobile devices use the 2.4 GHz frequency. Wi-Fi 6 with access points will support 802.11b/g/n clients and is the best choice even with an 11 Mbps data rate.
*Although Wi-Fi 6 uses both bands, a client can only use one radio at a time, not both. This is not a feasible possibility, even with a dual-band adapter.
~Wi-Fi 5 works only in the 5 GHz band. So any device using 2.4 GHz will not connect or even detect the device.
~802.11n is now officially designated as Wi-Fi 4 and can work over both 2.4 GHz and 5 GHz. However, many adapters only support a 2.4 GHz radio without a dual-band client adapter.
The network supervisor plans to predominantly use the 5 GHz band for an open plan office network. However, the business owner has heard that this has a shorter range and thinks the network supervisor should use the 2.4 GHz band. Why should the 5 GHz band be preferred over the 2.4 GHz band in this case? (Select all that apply.)
-Despite the open floor plan, 2.4 GHz has a shorter range than 5 GHz and would not work as well.
-Regulations on power and dynamic frequency selection (DFS) prevent signals from interfering with other nearby installations in a 5 GHz band.
-The chances of overlap are high on a 2.4 GHz band, increasing the risk of interference from other products.
-On a 2.4 GHz network, there is not enough space for separate networks.
Regulations on power and dynamic frequency selection (DFS) prevent signals from interfering with other nearby installations in a 5 GHz band, The chances of overlap are high on a 2.4 GHz band, increasing the risk of interference from other products, and On a 2.4 GHz network, there is not enough space for separate networks.
*In a 2.4 GHz network, each channel is only 5 MHz wide. Wi-Fi requires 20 MHz. The 5 GHz band is subdivided into 23 non-overlapping channels, each 20 MHz wide, reducing the risk of interference.
*In a 2.4 GHz band, there is no room for separate networks. Therefore, the chances of overlap/interference are high using the 2.4 GHz band products.
*There are regulatory limits on power output constraining ranges of Wi-Fi devices. The 5 GHz band must use DFS to prevent Wi-Fi signals from interfering with radar/satellite signals.
~An open plan does not have solid walls or building features to block signals. The slightly reduced range of 5 GHz (not 2.4 GHz) should not be a significant drawback.
