Chapter 3 vocabulary.txt

  1. 1000 Base-T
    A name for the IEEE Gigabit Ethernet standard that uses four-pair copper cabling, a speed of 1000 Mbps (1Gbps) and a maximum cable length of 100 meters.
  2. 100 Base-TX
    A name for the IEEE Fast Ethernet standard that uses two-pair copper cabling, a speed of 100 Mbps, and a maximum cable length of 100 meters.
  3. 10 Base-T
    The 10 Mbps baseband Ethernet specification using two pairs of twisted pair cabling (categories 3, 4, or 5).  One pair transmits data and the other receives data.  10 Base-T, which is part of the IEEE 802.3 specification, has a distance limit of approximately 100m (382 feet) per segment.
  4. Crossover Cable
    An ethernet cable that swaps the pair used for transmission on one device to a pair used for receiving on the device at the opposite end of the cable.  In 10 Base-T and 100 Base-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.
  5. CSMA/CD
    Carrier sense multiple access collision detect.  A media access mechanism in which devices ready to transmit data first check the channel for a carrier.  If no carrier is sensed for a specific amount of time a device can transmit.  If two devices transmit at once, a collision occures and it detected by all colliding devices.  This collision subsequently delays retransmissions from those devices for some random length of time.
  6. Full Duplex
    Generically, any communication in which two communicating devices can concurrently send and receive data.  In Ethernet LANs the allowance for both devices to send and receive at the same time allowed when both devices disable their CSMA/CD logic.
  7. Half Duplex
    Generically, any communication in which only one device at a time can send data.  In Ethernet LANs the normal result of the SCMA/CD algorithm that enforces the rule that only one device should send at any point in time.
  8. Hub
    A LAN device that provides a centralized connection point for LAN cabling, repeating any received electrical signal out all other ports, thereby creating a logical bus.  Hubs do not interpret the electrical signals as a frame of bits, so hubs are considered to be layer 1 devices.
  9. Pinout
    The documentation and implementation of which wires inside a cable connect to each pin position in any connector.
  10. Protocol Type Field *
    A field in a LAN header that identifies the type of head that follows the LAN header.  Includes the DIX ethernet type field, the IEEE 802.2 DSAP field and the SNAP protocol type field.
  11. Shared Ethernet
    An Ethernet that uses a hub or even the orignal coaxial cabling, whcih results in the devices having to take turns sending data, sharing the available bandwidth.
  12. Straight-through Cable
    In Ethernet, a cable that connects the wire on pin 1 on one end of the cable to pin 1 on the other end of the cable, pin 2 to pin 2 and so on.
  13. Switch
    A network device that filters, forwards and floods Ethernet frames based on the destination address of each frame.
  14. Switched Ethernet
    An Ethernet that uses a switch, and particularly not a hub, so that the devices connected to one switch port do not have to contend to use the bandwidth available on another port.  this term contrasts with shared Ethernet, in which the devices must share bandwidth, whereas switched Ethernet provides much more capacity, as the devices to not have to share the available bandwidth.
  15. Twisted Pair
    Transmission medium consisting of two insulated wires, with the wires twisted around each other in a spiral.  An electrical circuit flows over the wire pair, with the current in opposite directions on each wire, which significantly reduces the interferance between the two wire pairs.
  16. MAC
    Media Access Control.  802.3 (Ethernet) defines the MAC sublayer of IEEE ethernet.
  17. Ethernet, NIC, LAN Address
    Other names often used instead of MAC address.  These terms describe the 6-byte address of the LAN card.
  18. Burned in Address
    The six byte address assigned by the vendor making the card.
  19. Unicast Address
    A term for a MAC that represents a single LAN interface.
  20. Broadcast Address
    An address that means "all devices that reside on this LAN right now."
  21. Multicast Address
    On Ethernet, a multicast address implies some subset of all devices currently on the Ethernet LAN.
Card Set
Chapter 3 vocabulary.txt