User`s guide

Glossary
D-17
requirements and the encoding of data for transmission.
physical layer
Layer 1 of the OSI model. Defines and handles the electrical and
physical connections between systems.
PMD (Physical Layer Medium Dependent)
FDDI standard that defines the medium and protocols used to
transfer symbols between physical layer protocols.
power budget
The difference between transmit power and receiver sensitivity,
including any safety margins.
PPP (point-to-point protocol)
A protocol for transmitting datagrams (IP or MAC packets) over a
serial point-to-point link (e.g., the out-of-band management port).
pps (packets per second)
Unit of measure used to express packet data throughput. 18 pps is
approximately equal to 9600 bps.
propagation delay
The time it takes for a signal to travel across a network.
protocol
A set of rules used by computers and related devices to
communicate with each other.