User Manual

Glossary
229
Glossary
N
neighbor Adjacent system reachable by traversing a single subnetwork. An immediately adjacent
router. Also called a peer.
NET Network entity title. Network address defined by the ISO network architecture and used in
CLNS-based networks.
Network Time Protocol See NTP.
NIC Network Information Center. Internet authority responsible for assigning Internet-related
numbers, such as IP addresses and autonomous system numbers. See also IANA.
NSAP Network service access point. Connection to a network that is identified by a network
address.
n-selector Last byte of a nonclient peer address.
NTP Network Time Protocol. Protocol used to synchronize computer clock times on a network.
O
OC Optical Carrier. In SONET, Optical Carrier levels indicate the transmission rate of digital
signals on optical fiber.
OSI Open System Interconnection. Standard reference model for how messages are transmitted
between two points on a network.
OSPF Open Shortest Path First. A link-state IGP that makes routing decisions based on the
shortest-path-first (SPF) algorithm (also referred to as the Dijkstra algorithm).
P
package A collection of files that make up a JUNOS software component.
Packet Forwarding
Engine
The architectural portion of the router that processes packets by forwarding them between
input and output interfaces.
PCI Peripheral Component Interconnect. Standard, high-speed bus for connecting computer
peripherals. Used on the Routing Engine.
PCMCIA Personal Computer Memory Card International Association. Industry group that promotes
standards for credit card-size memory or I/O devices.
PDU Protocol data unit. IS-IS packets.
PE router Provider edge router. A router in the service provider's network that is connected to a
customer edge (CE) device and that participates in a Virtual Private Network (VPN).
peer An immediately adjacent router with which a protocol relationship has been established. Also
called a neighbor.
PFE See Packet Forwarding Engine.
Physical Interface Card See PIC.
PIC Physical Interface Card. A network interface–specific card that can be installed on an FPC in
the router.