M-P

---

Make Before Break

A procedure in which the back-up path is switched in before the failed path is switched out. For a small period of time, both the primary and back-up paths carry the traffic.

MIB

Management Information Base

MOS

Mean Opinion Score

MPLS

Multiple Protocol Label Switching; also Multiple Protocol Lambda Switching

NHLFE

Next Hop Label Forward Entry

Node Protection

A backup procedure in which a node is replaced in the event of a failure.

Ordered Control

A label-distribution method in which a designated label manager (most often the egress Label Edge Router) assumes responsibility for label distribution.

OSPF

Open Shortest Path First; a routing protocol

OSPF-TE

Open Shortest Path First with Traffic Engineering

O-UNI

Optical User Network Interface

Over-provisioning

Having more bandwidth than allocated traffic; allocating more assets (bandwidth) than are needed.

Over-subscribing

Having more allocated traffic than available bandwidth. (Telco)

PDU

Protocol Data Unit

PE

Provider Equipment; also Provider Edge

PPP

Point-to-Point Protocol

PPP/HDLCoMPLS

Point-to-Point/High-Level Data Link Control over MPLS

Pre-provisioned Path

A path in the switching database on which traffic engineering has been performed in order to accommodate traffic in case of a failure.

Pre-qualified Path

A path that is tested prior to switchover that meets the Quality of Service (QoS) standards of the primary path.

Primary Path

The path through which the traffic would normally progress.

Protected Path

A path for which there is an alternative back-up path.

---