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POTS
Plain Old Telephone Service - This is the term used to describe basic telephone
service.
PPP
Point to Point Protocol. PPP encapsulates and transmits IP (Internet Protocol)
datagrams over serial point-to-point links. PPP works with other protocols such as
IPX (Internetwork Packet Exchange). The protocol is defined in IETF (Internet
Engineering Task Force) RFC 1661 through 1663. PPP provides router-to-router,
host-to-router, and host-to-hostconnections.
PPPoE
PPP over Ethernet is a protocol for connecting remote hosts to the Internet over an
always-on connection by simulating a dial-up connection.
PSTN
Public Switched Telephone Network was put into place many years ago as a voice
telephone call-switching system. The system transmits voice calls as analog
signals across copper twisted cables from homes and businesses to neighborhood
COs (central offices); this is often called the local loop. The PSTN is a
circuit-switched system, meaning that an end-to-end private circuit is established
between caller and callee.
PVC
Permanent Virtual Circuit. A PVC is a logical point-to-point circuit between
customer sites. PVCs are low-delay circuits because routing decisions do not need
to be made along the way. Permanent means that the circuit is preprogrammed by
the carrier as a path through the network. It does not need to be set up or torn
down for each session.
