Defines a set of route patterns and/or directory numbers. Phones that can reach one route pattern within a partition can reach all route patterns within the partition.
A legacy type of telephony connection that allows more than one home to share the tip and ring wires going back to a CO.
permanent virtual circuit (PVC)
A virtual path through a Frame Relay or an ATM network.
A QoS mechanism that limits bandwidth used by an application, typically by dropping excess packets.
An external power supply for a Cisco IP phone.
Power over Ethernet (PoE)
The IEEE 802.3af standard for powering network devices over an Ethernet cable.
primary CallManager server
A CallManager server that IP phones register with by default.
private branch exchange (PBX)
A privately owned phone switch used by a large business.
A set of rules that determines how information is exchanged.
Public Safety Answering Point (PSAP)
Contains a public database of 911 information.
public switched telephone network (PSTN)
The national public telephone system.
A CallManager server that contains a read/write copy of the CallManager database and sends updates to subscriber servers.
pulse amplitude modulation (PAM)
A sampling method that takes samples consisting of a single frequency (that is, the carrier frequency), with amplitudes (that is, volumes) equaling the amplitudes of the sampled waveform at the instance of the sampling.
pulse code modulation (PCM)
The process of converting pulse amplitude modulation (PAM) samples into a digital format, which is used by the G.711 CODEC.
Opens and closes a tip and ring circuit very rapidly, which represents dialed digits to a telephone switch.