Levels Of Service; Strata Dk's Tspi Model - Toshiba Strata DK40 Installation & Maintenance Manual

Levels of Service

Levels of Service
Basic
Basic Services are centred around Plain Old Telephony Service (POTS) including a set of
re-defined call states and information messages which pass events to the applications.
Features of POTS include answering calls, making calls, numbering plans to support dialling
and the ability to translate numbers based upon type and location of the user.
Supplementary
Supplementary Services provide additional features commonly found in most PBXs. These
include call features such as Call Transferring, Forwarding, Conferencing, Hold, Park and
Pickup. Additional services are defined for interfacing Media Services such as providing
interfaces for fax, modems, voice response and tone detection/generation. Release 2.0 of the
TAPI specification includes third party call control services for Automatic Call Distribution
(ACD) and future Asynchronous Transfer Mode (ATM), type services.
Extended
Extended Services provide a method to access features and services beyond the Basic or
Supplementary Services. TAPI provides for the passing of messages directly between the
telephone system and the application. TAPI only passes these messages directly to either end
and does not take action or make interpretations of them. The application, therefore is
responsible for the complete interaction of the feature or service provided.
Interfaces
The Windows Open System Architecture provides two interfaces for Telephony Devices.
The TAPI interface provides for the control of calls using a well defined interface and the
audio connection is handled in what Microsoft calls a Media Stream. To allow for a standard
interface for playing and recording messages, interfacing fax, modem or other devices, a
separate application interface is used. The AV API is a common interface that can provide
these services in an open manner that can be controlled using the TAPI interface.

Strata DK's TSPI Model

For the application's developer, the Microsoft standard provides for two device classes: the
line device and the phone device. Any physical telephonic device recognised by TAPI fits
into one of these two classes and can be treated in a consistent and reliable manner. Strata
DK TSPI only supports the line device class. The phone class is for telephone devices
controlled by the application.
Line Device Model
The Strata DK TSPI models its interface as a single-line device with multiple addresses, each
having no more than one call appearance. The specific capabilities of the line device and
each of the addresses are explained under the function description for lineGetDevCaps and
lineGetAddressCaps.
Phone Device Model
At present, the DKT TSPI does not support the phone device model.
Strata DK40 I&M Manual Spring 1999
Refer to the Strata DK40 Programming Manual or DK Library CD-Rom for more details.
Computer Telephony Integration
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