1.5 Compare and contrast transmission media and transceivers Flashcards
(14 cards)
An engineer is installing a new connection between two database stacks. The engineer is using copper cable and needs a connection speed of 40GbE with a distance of about 12 feet.
Which medium should the engineer utilize for this link?
- 10Base-T
- 10GBase-LR
- Twinaxial
- Coaxial
- Twinaxial
Twinax is for data center 10 GbE (unofficially referred to as 10GBASE-CR) and 40 GbE (40GBASE-CR4) interconnections of up to about 5 meters for passive cable types and 10 meters for active cable types.
Coaxial/RG-6 is an 18 AWG cable with 75-ohm impedance typically used as drop cable for Cable Access TV (CATV) and broadband cable modems.
A 10GBASE-LR is rated for 10 km operation over single mode fiber.
A 10BASE-T denotes an early implementation that works at 10 Mbps (10), uses a baseband signal (BASE), and runs over twisted pair copper cabling (-T).
An IT engineer chooses to use a fiber cable implementation that uses light-emitting diode (LED) technology rather than one that uses lasers.
Considering the optic technology in use, what is the engineer implementing?
- Single-mode
- Duplex
- Multimode
- Bidirectional
- Multimode
Multimode fiber is inexpensive to deploy compared to single-mode fiber. As such, it does not support long distances as single-mode. Multimode uses light emitting diode (LED) technology.
Single-mode cables support data rates up to 10 Gbps or better and cable runs of many kilometers, depending on the quality of the cable and optics.
Duplex is a communication configuration. Full duplex refers to a communication configuration/type such as network links that allow simultaneously sending and receiving. Most network links are full-duplex.
Bidirectional refers to two-way communication. Bidirectional does not imply the ability for full-duplex and may only be half-duplex. This means send and receive is taken in turns.
Which of the following 802.11 standards will provide the fastest wireless network throughput and work in the 5 GHz band only?
- 802.11b
- 802.11g
- 802.11n
- 802.11ac
- 802.11ac
The 802.11ac standard is one of the latest standards other than 802.11ax that are available for consumers today. It is designed to work only in the 5 GHz band and can provide a gigabit-like network throughput.
The 802.11b standard is a legacy standard that provides data rates of 11 Mbps and works in the 2.4 GHz band.
The 802.11g standard is also a legacy standard that became a straightforward upgrade path from 802.11b. It has a nominal data rate of 54 Mbps and works in the 2.4 GHz band.
The 802.11n standard is the predecessor to 802.11ac. It can use channels in the 2.4 GHz and 5 GHz band. It also offers channel bonding.
An engineer has installed a new router but is not connected to the core network yet.
What type of connector should the engineer install to get the requested throughput of 30Gbps or more?
- Dense wavelength division multiplexing (DWDM)
- Enhanced quad small form-factor pluggable (QSFP+)
- Coarse wavelength division multiplexing (CWDM)
- Enhanced form-factor pluggable (SFP+)
- Enhanced quad small form-factor pluggable (QSFP+)
Enhanced quad small form-factor pluggable (QSFP+) supports 40 GbE by provisioning 4 x 10 Gbps links.
Enhanced form-factor pluggable (SFP+) is an updated specification to support 10 GbE but still uses the LC form factor.
Dense Wavelength Division Multiplexing (DWDM) provisions greater numbers of channels (20, 40, 80, or 160). This means that there is much less spacing between each channel and requires more precise and expensive lasers.
Coarse Wavelength Division Multiplexing (CWDM) supports up to 16 wavelengths and is typically used to deploy four or eight bidirectional channels over a single fiber strand.
An organization has asked a junior network technician to retrieve some swappable ports that host a single LC connection per port.
Since there are numerous inserts for network devices, which should the technician retrieve?
- F-type connector
- SFP
- RJ-45
- QSFP
- SFP
Also designed for Gigabit Ethernet, the small form-factor pluggable (SFP) uses local connectors (LCs). Gigabit Interface Converter (GBIC) was very bulky and largely replaced by SFP, also known as mini-GBIC.
Quad small form-factor pluggable (QSFP) is a transceiver form factor that supports 4 x 1 Gbps links, typically aggregated to a single 4 Gbps channel.
RG-6 is an 18 AWG cable with 75-ohm impedance typically used as a drop cable for Cable Access TV (CATV) and broadband cable modems, and usually terminated using F-type connectors secured by screwing into place.
Technicians use RJ-45 connectors with 4-pair (8-wire) cables. The connectors are also known as 8P8C (8-position/8-contact).
Users at a company use a mix of wireless devices (phones, tablets, laptops) that use either the 2.4 or 5 GHz spectrum.
Considering the given wireless 802.11 standard, which one does the company utilize for their mobile devices?
- b
- a
- n
- g
- n
802.11n products can use channels in the 2.4 GHz band or the 5 GHz band, although the 5 GHz band is preferred for optimal bandwidth and to avoid interference.
802.11b standardized the use of the carrier method Direct Sequence Spread Spectrum (DSSS), uses the 2.4 GHz band, and operates at 11 Mbps.
The 802.11a has a nominal data rate of 54 Mbps and is an older wireless specification that was released in 1999. It uses only the 5 GHz band.
802.11g uses the 2.4 GHz band and has a nominal data rate of 54 Mbps. When in 802.11b compatibility mode, it drops back to using DSSS.
The T11 ANSI standard can be a particularly expensive way to connect a Storage Area Network (SAN) and involves three main types of components: the initiator, the target, and a director.
What is the name of the standard described?
- Fibre channel
- Application layer
- Internet Small Computer Systems Interface (iSCSI)
- North-South
- Fibre channel
The Fibre Channel connects storage area networks using 3 main types of components: the initiator, the target, and the Fibre Channel switch. The initiator is the client device of the SAN. The target is the network port for a storage device. The Fibre Channel switch, sometimes referred to as a director, provides the connections between the initiator and the target.
The application layer is part of the infrastructure of software-defined networking. It applies the business logic that makes decisions about how to prioritize and secure traffic and where to switch the traffic.
North-South describes data traveling into and out of a data center.
Internet Small Computer Systems Interface (iSCSI) does not require a Fibre Channel switch.
technician is building a new network link between a switch and a router. The switch only has ethernet ports, while the router only has fiber ports.
What could the technician utilize to connect these two devices?
- SFP+
- Patch panel/ patch bay
- Transceiver / Media converter
- Fiber distribution panel
- Transceiver / Media converter
The same hub has Host A1 and Host B1 connected. Host A1 sends a request to communicate with Host C2. Host B1 is communicating with Host C3. There is a delay in communications between Hosts A1 and C2 until the media is clear.
Which Ethernet protocol is providing this function?
- Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
- VLAN
- Broadcast domain
- Carrier Sense Multiple Access/Collision Detection (CSMA/CD)
- Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol uses schemes, such as “request to send,” to gain access to the media. Nodes listen to the media before transmitting and transmit when the media is clear. A node wanting to transmit but detecting activity, must wait and try later.
CSMA with Collision Detection (CSMA/CD) protocol defines methods for detecting a collision. When a signal present on the interface transmits and receives lines simultaneously, the node broadcasts a jam signal.
Virtual Local Area Network (VLAN) creates separate layer 2 broadcast domains on the same switch or configures separate broadcast domains across distributed switches.
Nodes that share the same broadcast address are within the same broadcast domain.
A cable installer uses snips to cut the cable and strip the insulation to install connectors.
What single tool can the installer use to do this when working with multiple types of cable?
- Fusion splicer
- Cable stripper
- Cable crimper
- Test access point (TAP)
Cable stripper
A tech replaces a failed wireless router at a company. While waiting for the new router to arrive, an older router is put in place and will only provide speeds of 54 Mbps.
Which wireless standard does the older router use?
- n
- ac
- g
- b
- g
802.11g uses the 2.4 GHz band and has a nominal data rate of 54 Mbps. When in 802.11b compatibility mode, it drops back to using DSSS.
802.11b standardized the use of the carrier method Direct Sequence Spread Spectrum (DSSS), uses the 2.4 GHz band, and operates at 11 Mbps.
The 802.11ac standard continues the development of 802.11n technologies. The main distinction is that 802.11ac works only in the 5 GHz band.
802.11n products can use channels in the 2.4 GHz band or the 5 GHz band, although the 5 GHz band is preferred for optimal bandwidth and to avoid interference.
Network equipment in a rack system has limited in-front-facing space with the door closed. A technician uses small form-factor connectors to connect a fiber cable.
Which of the following connector types is the technician using?
- APC
- LC
- UPC
- SC
- LC
A network installer is building a long-distance link. The nodes are approximately 5 km apart.
What type of fiber link should the installer build for this link?
- 100BASE-SX
- 10GBASE-SR
- 1000BASE-LX
- 100BASE-FX
- 1000BASE-LX
The 1000BASE-LX is a Gigabit Ethernet standard and supports 1 Gbps and a distance of 5 km using single mode fiber.
Installers often use the 100BASE-FX Fast Ethernet firer standard for wiring backbones. It uses multimode fiber for speeds of up to 100Mbps for a distance of up to 2 km.
The 100BASE-SX is a Fast Ethernet fiber standard that supports lengths up to 300 meters and speeds up to 100Mbps.
The 10GBASE-SR is a 10 Gigabit Ethernet fiber standard in backbone configurations, and it supports up to 300-meter link lengths.
