physical media (medium)
Cabling & connectors used to interconnect the network devices.
Optical or electrical impulse on a physical medium for purposes of communication.
To change the energy levels transmitted over some networking medium to transmit bits over that medium.
Time required to send a single bit over some transmission medium.
- Calculated as 1/speed
- (Speed = number of bits per second sent over the medium)
Non-Return to Zero
Line code represented by one significant condition and 0s are represented by another.
Line code in which each bit of data is signified by at least one voltage level transition.
Grouping of code that meets a certain specified condition for entering in that certain group.
Uses 5-bit symbols or codes to represent 4 bits of data
Used in 100BASE-TX Ethernet
Unit of measurement of the number of times 1000 bits can be transmitted in 1 second.
1kbps = 1000bps
Unit of measurement of the number of times 1,000,000 bits can be transmitted in 1 second.
1 Mbps = 1,000,000 bps
Actual data transfer rate between two computers at some point in time.
Impacted by the slowest-speed link used to send data between the two computers.
(In addition to any other outside factors.)
Number of useful bits per unit of time from a certain source address to a certain destination.
Excluding protocol overhead & retransmitted data packets.
Loss of communication signal on the media.
Due to degradation of the energy wave over time.
General term referring to any energy signal on a transmission medium that is not part of the signal used to transmit data over that medium.
Unshielded Twisted-Pair cable
General type of cable, cable holds twisted pairs of copper wires and the cable itself having little shielding.
A rectangular cabling connector with eight pins, often used with Ethernet cables.
Defines which wires in a cable should connect to each pin on the connectors on both ends of a cable.
UtP cable pinout that specifies that the wire at pin 1 connects to pin 1 on the other end, pin 2 to pin 2, pin 3 to pin 3, etc.
EX: connecting PC to hub or switch
UTP cable used in Ethernet
Some pairs of twisted-pair wires are crossed at either ends of the RJ-45.
Cisco proprietary cable
UTP pinout that specifies RJ-45 pinout connects pin 1 to pin 8, pin 2 to pin 7, pin 3 to pin 6, etc.
Cisco console cables for routers and switches.
coax / coaxial cable
Consisting of a hollow outer cylindrical conductor that surrounds a single inner wire conductor.
- Three different layers of material surrounding the inner conducting material:
- the outer conductor
- the insulator
- the protective outer jacket
Network that incorporates both optical fiber along with coaxial cable to create a broadband network.
Shielded Twisted-Pair cable
Type of network cable that includes twisted-pair wires, with shielding around each pair of wires,, as well as another shield around all wires in the cable.
Physical medium that uses glass or plastic threads to transmit data.
Transmit data via light waves.
Certification method for fiber.
Tool for testing fiber measuring the time to shine in one end and out the other noting the imperfections in between.