Cisco Systems 78-11450-03 specifications See OIR, GL-9

	Glossary
Multicast	Single packets copied by the network and sent to a specific subset of network addresses. These
	addresses are specified in the Destination Address field. Compare with Broadcast and Unicast.
Multilink	See MLP.
Point-to-Point
Multimode fiber	See MMF.
Multiplexing	An activity in which multiple logical signals are transmitted simultaneously across a single physical
	channel.
Multiprotocol Label	See MPLS.
Switching
N
NEBS	Network Equipment Building Systems. The Telcordia (formerly Bellcore) requirements for equipment
	deployed in a central office environment. Covers spatial, hardware, crafts person interface, thermal, fire
	resistance, handling and transportation, earthquake and vibration, airborne contaminants, grounding,
	acoustical noise, illumination, EMC, and ESD requirements.

Network Equipment Building Systems

Network termination unit

Nonvolatile RAM

NTU

NVRAM

See NEBS.

See NTU.

See NVRAM.

Network terminating unit. The network equipment that connects directly to the data terminal equipment.

Nonvolatile RAM. RAM that retains its contents when a unit is powered off.

O

OC	Optical carrier. A series of physical protocols (OC-1, OC-2, OC-3, and so forth), defined for SONET
	optical signal transmissions. OC signal levels put STS frames onto fiber-optic lines at a variety of
	speeds. The base rate is 51.84 Mbps (OC-1); each signal level thereafter operates at a speed divisible
	by that number (thus, OC-3 runs at 155.52 Mbps).

ODL

OIR

Optical data link.

Online insertion and removal. Feature that permits the addition, replacement, or removal of cards without interrupting the system power, entering console commands, or causing other software or interfaces to shut down. Same as hot-swapping.

Online insertion and		See OIR.
removal
		Cisco uBR10012 Universal Broadband Router Hardware Installation Guide
	78-11450-03 Rev.B0		GL-9