Cisco Systems OL-4387-02 manual GL-3

Glossary

P

permanent virtual	A fixed virtual circuit between two users. The public data network equivalent of a leased line. No call
circuit	setup or clearing procedures are needed.
point-to-point	With point-to-point subinterfaces, each pair of routers has its own subnet. If you put the PVC on a
subinterface	point-to-point subinterface, the router assumes that there is only one point-to-point PVC configured on
	the subinterface. Therefore, any IP packets with a destination IP address in the same subnet are
	forwarded on this VC. This is the simplest way to configure the mapping and is, therefore, the
	recommended method.
port	The abstraction used by Internet transport protocols to distinguish among multiple simultaneous
	connections to a single destination host.
PPP	Point-to-Point Protocol. The successor to SLIP, PPP provides router-to-router and host-to-network
	connections over both synchronous and asynchronous circuits.
PPPoA	PPP over ATM. Enables a high-capacity central site router with an Asynchronous Transfer Mode
	(ATM) interface to terminate multiple remote PPP connections.
PPPoE	PPP over Ethernet. Allows a PPP session to be initiated on a simple bridging Ethernet connected client.
	Refers to a signaling protocol defined within PPPoE as well as the encapsulation method. See also
	RFC 2516.
PPPoEoA	PPP over Ethernet over ATM. Allows tunneling and termination of PPP sessions over Ethernet links
	and allows for Ethernet PPP connections over ATM links.
PPPoEoE	PPP over Ethernet over on Ethernet. Allows tunneling and termination of PPP sessions over Ethernet
	links and allows for Ethernet PPP connections over Ethernet links.
PPPoEo802.1Q	PPP over Ethernet over IEEE 802.1Q VLANs. Allows tunneling and termination of Ethernet PPP
VLAN	sessions across VLAN links. IEEE 802.1Q encapsulation is used to interconnect a VLAN-capable
	router with another VLAN-capable networking device. The packets on the 802.1Q link contain a
	standard Ethernet frame and the VLAN information associated with that frame.
PPPoX	PPP over PPPoA or PPPoE or both.
PTA	PPP terminated aggregation. A method of aggregating IP traffic by terminating PPP sessions and
	aggregating the IP traffic into a single routing domain.
PTA-MD	PTA-Multidomain. A method of aggregating IP traffic by terminating PPP sessions and aggregating the
	IP traffic into a VPN or multiple IP routing domains. For an ISP, the aggregated traffic either remains
	in the ISP network or routes to the Internet. For a wholesale provider, the aggregated IP traffic is
	forwarded to different destinations or domains depending on the service selected; thus the term
	PTA-Multidomain.
PVC	Permanent virtual circuit or connection. Virtual circuit that is permanently established. PVCs save
	bandwidth associated with circuit establishment and tear down in situations where certain virtual
	circuits must exist all the time. In ATM terminology, called a permanent virtual connection. Compare
	with SVC. See also virtual circuit (VC).

Cisco 10000 Series Router Service Selection Gateway Configuration Guide

OL-4387-02 GL-3