Cabling and Topology Flashcards
What is a topology?
Ways of connecting computers together
What is a network topology?
Way that cables and other pieces of hardware connect to one another
What are the 3 historical topologies?
- Bus
- Ring
- Star
What are the two modern topologies?
- Hybrid
2. Mesh
Describe a bus topology.
Network using a single cable to connect all computers in a line
Describe ring topology.
Network connected in a ring by a cable, where the date moves in a circle in the same direction
Why does the bus topology require termination at each end of the cable?
To prevent signal from reflecting at the ends
What do bus and ring topologies suffer from?
The entire network stops working if the cable breaks at any point
Describe a star topology.
Central connection box for all computers on a network
What does star topology offer that bus and ring do not?
Fault tolerance
Describe fault tolerance.
If one cable breaks, all the computers could still communicate
What is physical topology?
How the cables physically look
What is logical topology?
How the signals travel electronically
Describe mesh topology.
Network where every computer connects to every other computer via two or more routes
What are the two types of meshed topologies?
- Partially meshed
2. Fully meshed
Describe partially meshed topology.
At least two machines have redundant connections, but every machine does not have to connect to every other machine
Describe fully meshed topology.
Every computer connects directly to every other computer
What is network technology?
Practical application of a topology and other critical technologies that provide a method to get data from one computer to another on a network
What kind of cabling uses copper wire wrapped up in some kind of protective sheathing?
Copper cables
What are the two primary types of copper cabling used in the industry?
- Coaxial
2. Twisted pair
What is coaxial cable?
Contains a central conductor wire surrounded by an insulating material that is surrounded by a braided metal shield
What does coaxial cable do?
Fields data transmissions from interference(EMI)
What is an F-connector?
Type of cable connector that screws on, Making for a secure connection
What is an Ohm rating?
Relative measure of resistance on a cable
What is impedance?
Set of characteristics that define how much a cable resists the flow of electricity
What is capacitance?
How long it takes the wire to get a full charge
What are the Ohm rating, connector type and use of RG-58 coaxial cables?
Ohm rating: 50
Connector: BNC
Use: Networking
What are the Ohm rating, connector type and use of RG-59 coaxial cables?
Ohms: 75
Connector: F Type
Use: Cable TV
What are the Ohm rating, connector type and use of RG-6 coaxial cables?
Ohms: 75
Connector: F Type
Use: Cable TV
What are the two types of twisted-pair cabling?
- Shielded
2. Unshielded
Describe Shielded Twisted Pair(STP).
Consists of two pairs of wires surrounded by shielding to protect them from EMI
What are the 6 types of STP?
- F/UTP
- S/UTP
- SF/UTP
- S/FTP
- F/FTP
- U/FTP
Describe Unshielded Twisted Pair(UTP).
Consists of two pairs of wires surrounded by a plastic jacket; does not provide any protection from EMI
Describe F/UTP.
Foil shields the entire cable; inside, the wires are just like UTP
Describe S/UTP.
A braid screen shields the entire cable; inside, the wires are just like UTP
Describe SF/UTP.
A braid screen and foil shields the entire cable; the wires inside are just like UTP
Describe S/FTP.
A braid screen shields the entire cable; foil shields each wire pair inside
Describe F/FTP.
Foil screen shields the entire cable; flood shields each wire pair inside
Describe U/FTP.
No overall shielding; each pair inside is shielded with foil screens
What are Category (Cat) ratings?
Variety of grades of cable used by the cabling industry
What are Cat ratings officially rated in?
Megahertz (MHz)
What are the 4 Cat ratings recognized by the Telecommunications Industry Association(TIA)?
- Cat 3
- Cat 5e
- Cat 6
- Cat 6a
What are the max frequency and bandwidth of Cat 3 cables?
Frequency: 16 MHz
Bandwidth: 16 Mbps
What are the max frequency and bandwidth of Cat 5e cables?
Frequency: 100 MHz
Bandwidth: 1 Gbps
What are the max frequency and bandwidth of Cat 6 cables?
Frequency: 250 MHz
Bandwidth: 10 Gbps
What are the max frequency and bandwidth of Cat 6a cables?
Frequency: 500 MHz
Bandwidth: 10 Gbps
What is bandwidth?
Maximum amount of data that goes through a cable per second
What does 8P8C stand for?
8 position 8 contact; it is the current connector used on wires networks( sometimes referred to as RJ-45 connectors)
Describe fiber optic cables.
Transmit light rather that’s electricity, making it attractive for both high-EMI areas and long distance transmissions
What is the theoretical max distance that fiber optic cabling can operate at?
Distances up to tens of kilometers
What are the four components of fiber optic cables?
- Core
- Cladding
- Buffer
- Insulating jacket
What is cladding?
Part of fiber optic cable that makes the light reflect down the fiber
What is the most common fiber optic cable size?
62.5/ 125 micro
What is a multimode fiber(MMF)?
Fiber optic cable that uses LED’s
What is a single mode fiber (SMF)?
Fiber optic cable that uses lasers
Describe modal distortion.
Signals sent at the same time don’t arrive at the same time because the paths differ slightly in length
What does it mean when connectors are duplex?
Both the send and receive cables are attached
What are fire ratings?
Define the risk of network cables burning and creating noxious fumes and smoke
What are the two most common fire ratings?
- PVC
2. Plenum
What is PVC?
Polyvinyl chloride - rating has no significant fire protection; creates a lot of smoke and noxious fumes
Describe Plenum-rated cable.
Creates much less smoke and fumes than PVC but Costa about three to five times as much
What is a plenum?
Space between the acoustical tile ceiling and the actual concrete ceiling above
What is the third type of fire rating?
Riser - designated proper cabling to use for vertical runs between floors and a building
What is the IEEE?
Institute of Electrical and Electronics Engineers - defines the industry wide standards that promote the use and implementation of technology
What is the IEEE 802.1 subcommittee?
Higher layer LAN protocols
What is the 802.11 subcommittee?
Wireless LAN(WLAN); specifications such as Wi-Fi
What is the IEEE 802.15 subcommittee?
Wireless Personal Area Network (WPAN)
Which of the following topologies required termination? A. Star B. Bus C. Mesh D. Ring
B. Bus
Star-bus is an example of a ________ topology?
Hybrid
Of the topologies listed below, which is the most fault tolerant? A. Point-to-point B. Bus C. Star D. Ring
C. Star
What term is used to describe the inter connectivity of network components?
Topology
Coaxial cables all have an __________ rating.
Ohm
Which of the following is a type of coaxial cable? A. RJ-45 B. RG-59 C. BNC D. Barrel
B. RG-59
Which network topology connected nodes with a ring of cable?
Ring
Which network topology is most commonly seen in wireless networks?
Mesh
Which of the following is a duplex fiber-optic cable? A. LC B. RJ-45 C. ST D. SC
A. LC
What is the most common category of UTP used in new cabling installations?
Cat 5e
