MPE/iX Glossary of Terms and Acronyms (32650-90887)

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Glossary of Terms
network.
packet switching A data communications transmission technique. Long messages are
divided into smaller packets and sent on a dynamically allocated path to
their destination.
packet switching network Refer to value added network.
page In MPE/iX a page is defined as a set of 2048 contiguous bytes (2KB) that is
used as the basic unit for memory mapping. All swapping is done in
multiples of pages.
parallel devices A set of backup devices to which you are able to store information
simultaneously.
parallel interface An interface type in which a separate line is used for each data bit in
a byte or word, and all of those bits are transferred simultaneously.
parameter A value in a list of values that is passed to a procedure. The parameter is
used in calculations or operations in the procedure.
parent process An existing process that creates a subsequent process, thereafter known
as the child process. A parent process may create one or more child
processes.
parity In computing, the condition of a bit being odd or even.
parity checking A form of redundancy checking during data transmittal. An odd or even
parity for a particular receiving device is selected. The sending device
checks the value of the parity bit to make sure it's the appropriate parity
for the receiving device. If the parity is not correct, the sending device adds
a 1 to the bit. The receiving device then checks the parity of the incoming
data, indicates any parity errors, and requests retransmission of data, if
necessary. Parity checking detects the loss, or unwanted inclusion, of an
odd number of bits.
parser A routine that subdivides an instruction, command, or programming
statement into components that the computer system can more easily
understand and use.
partitioning data See subdividing data.
Pascal A computer language that is used for many types of applications. It is a
very flexible language that is useful when different structures of data
types are needed.
password A string of ASCII characters required for a user to log on to a particular
group or account. Passwords are associated with users, groups, and
accounts.
patch A piece of software code that corrects a defect.
path The course within a computer that a message takes, typically through
software protocol handlers.
performance tuning Essentially is a matter of locating a bottleneck and then
eliminating or reducing it.