Agilent Technologies J3972A, J3919A manual Agent, Alarm Indication Signal AIS, Asynchronous

Agent

A node (or software/hardware on a node) that supplies network management information.

Alarm Indication Signal (AIS)

An Alarm Indication Signal (AIS) is transmitted downstream when a major alarm condition such as LOS, LOF, or LOP is detected. Different AIS signals are sent depending on the level of the maintenance hierarchy.

ANSI (American National Standards Institute)

The United States coordinating organization for voluntary standards.

ASCII (American Standard Code for Information Interchange)

Seven bit code providing a total of 128 upper and lower case letters, numerals, punctuation marks, and control characters. Also referred to as CCITT Alphabet Number 5.

Asynchronous

A transmission process such that there is always an integer number of units between any two significant instances in the same signal but there is not always an integer number of units between significant instances in two independent signals.

Asynchronous Transfer Mode (ATM)

Asynchronous Transfer Mode (ATM) is a fast packet-switched technology based on fixed length cells. Data is divided into individual units and routed across an ATM network in a constant stream. Unused packets are filled with idle cells. Flexible bandwidth is possible with ATM - a service can use as many ATM cells as it needs. Voice, video, and data can be sent in a consistent manner over an ATM network, making ATM a valuable solution for many different services.

ATM Adaptation Layer (AAL)

The ATM Adaptation Layer isolates the higher layers from the specific characteristics of the ATM Layer and provides a way to map data from variable length frames into the fixed size of ATM cells. Different Adaptation layers are used (AAL-1, AAL-3/4, and AAL-5) to implement different types of service.

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