Chapter 2 - Ethernet LANs Flashcards
Ethernet
A series of LAN standards defined by the IEEE, originally invented by Xerox Corporation and developed jointly by Xerox, Intel, and Digital Equipment Corporation.
IEEE
Institute of Electrical and Electronics Engineers. A professional organization that develops communications and networking standards, among other activities.
Wired LAN
(LAN) that physically transmits bits using cables
Wireless LAN
(LAN) that physically transmits bits using radio waves.
Ethernet Frame
Ethernet data-link header and trailer, plus the data encapsulated between the header and trailer.
10BASE-T
10-Mbps two pairs of twisted-pair cabling (Categories 3, 4, or 5): IEEE 802.3 100 m (328 feet) per segment.
100BASE-T
IEEE Fast Ethernet standard that uses two-pair copper cabling, a speed of 100 Mbps, and a maximum cable length of 100 meters.
1000BASE-T
IEEE Gigabit Ethernet standard that uses four-pair copper cabling, a speed of 1000 Mbps (1 Gbps), and a maximum cable length of 100 meters.
Fast Ethernet
IEEE standards that send data at 100 megabits per second.
Gigabit Ethernet
IEEE standards that send data at 1 gigabit per second.
Ethernet Link
Physical link between two Ethernet nodes, no matter what type of cabling is used.
RJ-45
Cabling connector used for Ethernet cabling. RJ-45 allows the connection of eight wires.
Ethernet Port
Ethernet NIC or LAN switch, into which an Ethernet cable can be connected.
Networking Interface Card (NIC)
Provides the electronics and other functions to connect to a computer network. Today, most NICs are specifically Ethernet NICs, and most have an RJ-45 port, the most common type of Ethernet port.
Straight-Through Cable
Pin 1 on one end of the cable to pin 1 on the other end of the cable, pin 2 on one end to pin 2 on the other end, and so on.
Crossover Cable
In 10BASE-T and 100BASE-TX networks, this cable swaps the pair at pins 1,2 to pins 3,6 on the other end of the cable, and the pair at pins 3,6 to pins 1,2 as well.
Ethernet Address
A 48-bit (6-byte) binary number, usually written as a 12-digit hexadecimal number, used to identify Ethernet nodes (destination/source addresses) in an Ethernet network.
MAC Address
Data-link layer address that is required for every device that connects to a LAN. Ethernet MAC addresses are 6 bytes long and are controlled by the IEEE. Also known as a hardware address, a MAC layer address, and a physical address.
Unicast Address
Address in networking that represents a single device or interface, instead of a group of addresses (as would be represented by a multicast or broadcast address).
Broadcast Address
Address that represents all devices, and can be used to send one message to all devices. In Ethernet, the MAC address of all binary 1s, or FFFF.FFFF.FFFF in hex.
Frame Check Sequence
A field in many data-link trailers used as part of the error-detection process.
Transceiver
transmitter and receiver. process received energy signals to interpret as a series of 1s and 0s.
Multimode Fiber (MM)
Fiber cable - LEDs that emit multiple angles of light into the core of the cable
Single-Mode Fiber (SM)
Fiber cable - lasers that emit a single angle of light into the core of the cable
Electromagnetic Interference (EMI)
Interfering with the use of electricity to transmit data on the second cable.
Core
In fiber-optic cabling, the center cylinder of the cable, made of fiberglass, through which light passes.
Cladding
In fiber-optic cabling, the second layer of the cable, surrounding the core of the cable, with the property of reflecting light back into the core.
Fiber-Optic Cable
A type of cabling that uses glass fiber as a medium through which to transmit light.
