Specifications

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Cisco 1751 Router Software Configuration Guide
OL-1070-01
P
PBX
Private branch exchange. Privately-owned central switching office.
PCM
Pulse code modulation. Transmission of analog information in digital form through sampling and
encoding the samples with a fixed number of bits.
PLAR
Private line auto ringdown. PLAR connection associates a peer directly with an interface. This type of
service results in a call attempt to some particular remote endpoint when the local extension is taken
off-key.
POTS
Plain old telephone service. Basic telephone service supplying standard single-line telephones,
telephone lines, and access to the public switched telephone network.
POTS dial peer
Dial peer connected via a traditional telephony network. A software object that ties together a voice
port and the telephone number of a device attached to the port (also called local dial peer).
PSTN
Public Switched Telephone Network. PSTN refers to the local telephone company. Sometimes called
plain old telephone service (POTS).
PVC
Permanent virtual circuit. Virtual circuit that is permanently established and is torn down in situations
where certain virtual circuits must exist all the time. PVCs save bandwidth associated with circuit
establishment.
Q
QoS
Quality of service. Measure of performance for a transmission system that reflects its transmission
quality and service availability.
R
RSVP
Resource Reservation Protocol. A network protocol that enables routers to reserve the bandwidth
necessary for reliable performance.
RTCP
RTP Control Protocol. A protocol that monitors the QoS of an IPv6 RTP connection and conveys
information about the on-going session.
RTP
Real-Time Transport Protocol. RTP is designed to provide end-to-end network transport functions
for applications transmitting real-time data, such as audio, video, or simulation data, over multicast
or unicast network services.
S
SNMP
Simple Network Management Protocol. SNMP provides a means to monitor and control network
devices, and to manage configurations, statistics collection, performance, and security.
SVC
Switched virtual circuit. Virtual circuit that is dynamically established on demand and that is torn
down when transmission is complete.