Appendices C
ARP (Address Resolution Protocol)
A member of the TCP/IP protocol suite, ARP is the method by which a station’s MAC address is determined given a station’s IP (Internet Protocol) address.
Attenuation
A reduction in the strength of a signal; the opposite of gain.
Bandwidth
Bandwidth is the rate at which data can be transmitted over a channel, measured in bits per second. For example, Ethernet has a 10 Mbps bandwidth and FDDI has a 100 Mbps bandwidth. Actual throughput is almost always less than the theoretical maximum.
BPS
Bits per second. A measure of speed or raw data rate. Often combined with metric prefixes as in kbps (for thousands of bits per second) or Mbps (for millions of bits per second).
Bridge (Switch)
A device that links two or more networks that use the same OSI Data Link protocol. A bridge evaluates source and destination addresses to pass only frames that have a destination on the connecting network.
Broadcast
A message that is addressed to all stations on a network. For Ethernet networks, the MAC broadcast address is
FFFFFFFFFFFF.
Broadcast Storm
A situation in which a large number of stations are transmitting broadcast packets. This typically results in severe network congestion. This problem is usually a result of a misconfiguration.
Bus Topology
A bus topology is a network architecture in which all of the nodes simultaneously receive network traffic. Ethernet is a bus topology.
Byte
A collection of bits. A byte usually contains 8 bits.
Characteristic impedance
Characteristic impedance is the opposition (resistance and reactance) to signal propagation on a cable. It depends on the physical properties of a cable, which are determined at the time of manufacture. Manufacturing variations can cause slight differences in characteristic impedance for the same cable type.