Interphase ENTIA 5536 DM PRI, User Manual

Page: 232 / 244

Glossary
212
Interphase Corporation
PMC (PCI Mezzanine Card)
‹ A daughtercard form factor implemen-
tation of the PCI bus specification.
POTS (Plain Old Telephone Service)
‹
Conventional voice grade
service and cabling infrastructure.
PPP (Point-to-Point Protocol)
‹ A dial-up protocol that allows a
computer to use TCP/IP networking to connect remote access devices,
such as modems, to the Internet or other TCP/IP based networks.
PPP/MP (Point-to-Point Protocol/Multilink Protocol)
‹ See Multi-link
PPP .
PRI (Primary Rate Interface)
‹
A type of ISDN service that offers 23
B-channels at 64 Kbps and one D-channel at 64 Kbps (23B+D). In
Europe, PRI provides for 30 B-channels and two D-channels
(30B+1D).
Private Line
‹ Synonym for a leased line. Dial voice line that does
not terminate at the voice private automatic branch exchange or that
does not appear on other sets in a key system.
Protocols
‹ A set of rules that define how different computer systems
and other devices interoperate with each other.
PSTN
‹
Public Switched Telephone Network.
PVC (Permanent Virtual Circuit)
‹
A logical link whose endpoints
and class of service are defined by network management.
For Frame relay, analogous to an X.25 permanent virtual circuit, a
PVC consists of the originating frame relay network element address,
originating data link control identifier, terminating frame relay net-
work element address, and termination data link control identifier.
Originating refers to the access interface from which the PVC is initi-
ated. Terminating refers to the access interface at which the PVC stops.
Many data network customers require a PVC between two points.
QLLC (qualified logical link control)
‹
An X.25 protocol that allows
the transfer of data link control information between two adjoining
SNA nodes that are connected through an X.25 packet-switching data
network. The QLLC provides the qualifier
Q bit in X.25 data packets
to identify packets that carry logical link protocol information.
Q.921
‹
This is the link layer protocol for ISDN.
Q.931
‹
This is the network layer protocol for ISDN. Q.931 was
developed for out-of-band call control.
RAI (Remote Alarm Indication)
‹ PRI alarm, also known as Yellow
signal. This alarm indicates a carrier failure.