Synonym asynchronous operation.

A de facto standard for modem commands from an attached CPU, used in most 1,200 and 2,400 b/s modems.

Analog Terminal Adapter

Abbreviation for all trunks busy.

Abbreviation for asynchronous time-division multiplexing.

A (terminating) IMS-based NG9-1-1 Service Architecture provides transit, routing, and other services required to support citizen-to-authority multimedia emergency services between the originating network and the emergency authority, e.g., PSAP. The IMS-based NG9-1-1 Service Architecture includes the i3 Legacy Network Gateway and i3 Legacy PSAP Gateway.

Abbreviation for asynchronous transfer mode.

A virtual channel connection (VCC) or a virtual path connection (VPC). [T1.627-1993]

An association established by the ATM Layer to support communication between two or more ATM service users (i.e., two or more next higher layer entities or two or more ATM Management entities). The communication over an ATM Layer connection may be either bidirectional or unidirectional. When bidirectional, two virtual channel connections (VCCS) are used. When unidirectional, only one VCC is… (Read More →)

A transport system composed of a carrier system terminated by an ATM multiplexer at each end. The relationship between input and output, i.e., virtual circuits, cannot change on a per call basis, i.e., permanent virtual circuits only are supported. This device does not allow blocking or signal compression. [T
1. Rpt46-1996]