NMS Communication - Natural Access

Development Environment

Natural Access™ is a modular runtime and development environment for NMS Communications' voice, fax, and call processing applications. It provides a simple and consistent standard application programming interface (API) for integrating and presenting media and telecommunication capabilities to an application.

Natural Access standard features include telephony call control, voice record and playback, tone detection and generation, and industry-standard H.100/H.110 (CT Bus) switching support. Natural Access is extensible, seamlessly integrating fax, voice over IP, and speech recognition products to the environment.

The Natural Access development environment


Natural Call Control™ service minimizes telecommunications application development and maximizes system performance.

Full-duplex voice play, record, and edit functions simplify application development.

Support for multiple voice file formats, including .WAV and NMS' .VOX, increases application compatibility.

Universal tone detectors and generators allow integration with PBX switches, paging terminals, and other specialized equipment.

H.100/H.110 (CT Bus) switching enables industry-standard interoperability.

Extensive documentation, in PDF, and fully functional demonstration programs reduce development time and effort.

Parameterized digital signal processor (DSP) algorithms give developers the ability to tune DSP algorithms to any target environment.

Fully asynchronous thread-safe libraries maximize performance and support any multi-threaded software architecture.

Seamless fax integration enables high-value applications.

Operating system independence provides application portability and gives developers the broadest possible market reach.

Supports Alliance Generation,® Convergence Generation,™ QX,™ and TX™ hardware platforms.

Natural Call Control

Natural Call Control is a service that simplifies telephony integration by abstracting complex signaling protocols into a simple flexible API. Signaling protocols are parameterized, allowing applications to interoperate quickly and easily with multiple networks.

Application Programming Interface (API)

At the highest level, programmers can use a single protocol-independent API. The syntax and semantics for placing, answering, and releasing calls are identical, regardless of the signaling protocol. This greatly simplifies programming and system integration. Developers can capitalize on rapid and wide deployment with a single development effort. High-value features such as DNIS/ANI (Dialed Number Identification Services/ Automatic Number Identification) and CallerID are uniformly supported by the API, enabling feature-rich applications.

The following are example functions for the Natural Call Control API:

nccStartProtocol — begins execution of a given protocol on a port. Example protocols are MFC-R2, loopstart, DID.

nccPlaceCall — places an outbound call on a port.

nccAnswerCall — answers an inbound/offered call on a given port.

nccReleaseCall — releases the call on a given port.

nccTransferCall — transfers the call to a given number.

nccBlockCalls — blocks incoming calls on a given port.

nccGetCallStatus — retrieves call information such as DNIS/ANI and state.

Network Signaling Protocols

The Natural Access software supports multiple network signaling protocols. Each protocol is parameterized, giving developers the ability to adapt the protocol to multiple target environments worldwide. For example, the MFC-R2 protocol states and events are identical for all countries, but certain parameters, such as tone duration, vary. Natural Access exposes these parameters to the programmer, allowing the protocol to be adapted to different environments.

All Natural Call Control protocols execute on Alliance Generation (AG) and Convergence Generation (CG) boards. The embedded CPU coordinates the DSP signal detectors and generators so that call setup and teardown procedures execute wholly on the board. This minimizes host CPU overhead, leaving more power for application programs and features.

Call Control Primitives

Primitives are also provided to enable the application to interface with a proprietary switch or PBX. These functions include:

Digital signal detectors and generators

Tone detectors and generators

LAPD access (ISDN)


All Natural Access signaling protocols are built from these primitives. The developer uses them to integrate with virtually any equipment.

Example call control primitives include:

nccAssertSignal — asserts a given signaling bit pattern for four bits (ABCD).

nccStartSignalDetector — enables a detector which generates events as signaling bits change.

nccStartTimer — enables a 10-ms resolution on-board timer.

Voice Functions

Natural Access' voice functions are a full-featured suite of record and playback capabilities. Developers can use high-level voice file functions or application-controlled voice buffering for lower level control. Multiple voice-encoding formats are supported to optimize application compatibility or performance.

The Natural Access voice service is open and extensible. Custom compression algorithms, file formats, and storage devices can be defined by developers and integrated beneath the Natural Access API. This allows a migration path from legacy systems and an evolutionary path to future technologies.

Application-controlled full-duplex voice buffering gives maximum control over supported vocoders and is ideally suited for voice over IP, host-based speech recognition, and LAN-enabled voice applications. The full-duplex voice support includes the echo-canceled low-latency voice streams required by these applications.

The Natural Access Prompt Builder is based on the .VOX indexed file format. This function accepts common interactive voice response strings such as dates, numbers, or monetary units and converts them into a sequence of voice messages.

Syntrillum Software Corporation's CoolEdit96™ graphical voice editor is included with Natural Access. CoolEdit96, which runs on Microsoft Windows 95 and Windows NT, simplifies prompt creation by allowing developers to graphically trim silence, cut-and-paste audio samples, and filter noise. CoolEdit96 also simplifies voice file conversion with support for NMS voice coding formats as well as OKI, .WAV, PCM, and other industry-standard formats.

Voice Features:

High-level file play, record, and edit functions reduce time to market.

Application-controlled voice buffering allows integration with asynchronous file system.

User-extensible file formats and devices support custom integration.

Prompt Builder reduces development time for interactive systems, creates professional- sounding prompts by eliminating delays between utterances, and simplifies international deployment of end systems.

Syntrillum Software Corporation's CoolEdit96 simplifies professional-quality voice prompt creation.

Industry standard voice encoding, such as 11-kHz, 8/16-bit linear (.WAV), ITU-T G.726, A-law, and µ-law, increases application compatibility.

NMS' ADPCM (optimized G.721 variant), maximizes DSP and disk efficiency while maintaining toll-quality voice.

Support for 8-kHz and 6-kHz OKI ADPCM provides a migration path from voice messages stored on legacy systems.

Playback speed and volume control allows dialed-in users to quickly step through voice messages and adjust volume by entering DTMF digits.

Automatic gain control adjusts the signal level so voice is captured at a normalized level when recording.

G.165 and G.168 compliant echo cancellation.

Reduced interrupts minimize host overhead.

Universal Tone

Natural Access supports Universal Tone capabilities. These are application-programmable, DSP-based tone detectors and generators that provide a high degree of accuracy and speed.

Multiple programmable tone detectors and generators support integration with a PBX or specialized equipment.

Simplified telephone signaling supports an idle period and repeat count for defining signal cadences.

Pre-programmed DTMF and MF detectors simplify common tasks.

1200 baud FSK (Frequency Shift Keying) modem allows ASCII transmit and receive for ADSI (Analog Display Services Interface) display telephones or short message services (SMS) in wireless applications


Natural Access includes an integrated switching API. The Natural Access switching services support two control levels for different application developer needs. The MVIP-95 driver API controls Mitel's Flexible MVIP Integrated Circuit (FMIC™) or Lucent's Ambassador™ TDM switching integrated circuits. This API is ideally suited for developers requiring a high degree of control over the TDM bus resources. The circuit-routing API provides a higher level of functionality, enabling the application developer to connect any two arbitrary devices attached to the switching interface. Natural Access further simplifies application development by managing the TDM bus resources.

Single API for analog, digital, and DSP devices simplifies programming and reduces development time.

Switching API supports both MVIP-90 driver standard for backward compatibility and MVIP-95 driver standard for future migration.

MVIP-95 standard supports all industry hardware standards including MVIP-90,H-MVIP, H.100, H.110, and MC1 multi-chassis operation.

Multi-access APIs support all developers' needs including open driver-level APIs for the highest degree of control and circuit-routing APIs for TDM bus resource management and simplified application development.

Operating System Independence

The Natural Access APIs are operating system independent. After an application is developed on a specific operating system, it can be ported to any of the other supported operating systems with no impact on the application program. The Natural Access architecture does not, however, preclude the developer from capitalizing on desired operating system features such as system-specific event-triggering functions. System developers can adapt their products for the broadest possible market, or can tailor the system uniquely for specific markets.


Natural Access' extensive documentation reduces system development time and enables more application features.

The Developer's Guide exposes Natural Access' underlying architecture, facilitating the learning and use of the product and allowing developers to capitalize on product features.

Electronic format improves workgroup productivity by allowing a single shared copy of on-line documentation. Links are provided between related functions and appendices.

Multiple standalone demonstration programs exhibit functions in detail, allowing accurate error-free programming.


Operating Systems

Windows NT 4.0

Windows 2000

SPARC Solaris

Intel Solaris

System Requirements

Bus: PCI, CompactPCI

Platforms Supported

AG 2000, AC 2000C, AG 4000, AG 4000C, AG Quad T, AG Quad E, CompactPCI Quad T, CompactPCI Quad E, CG 6000, CG 6000C, CG 6100C, CX 2000, CX 2000C, QX 2000, TX 3220, and TX 3220C

Voice Encoding Formats

NMS 16 kHz, 24 kHz, and 32 kHz ADPCM (optimized G.721 variant) supporting playback rate and volume control

G.711 64 kHz PCM


ITU-T µ?law and A-law

Linear PCM (.WAV) (8 kHz and 11 kHz) þ8-bit mono, 16-bit mono

OKI 6 kHz and 8 kHz

Natural Call Control Network Protocols

ISDN PRI (multiple US domestic and international variants)

CAS (multiple variants)

See ISDN and Digital CAS datasheets for complete list.

Demonstration Programs

Message tracing utility

Hardware management utilities

Parameter management utilities

Interactive test and demonstration

Call control: inbound calls, outbound calls, transfers, blocking

Asynchronous and synchronous voice recording and playback

AG board detection and MVIP configuration per AG board

Various application software architectures