# NaturalFax definition

NaturalFax is a C function library component of Natural Access that provides fax functionality. Use NaturalFax to produce fax server products for enterprise fax applications, IP telephony gateways, and large scale fax service provider systems. Applications include LAN fax, fax broadcast, fax-on-demand, store-and-forward, and realtime fax-over-IP data networks. NaturalFax applications can transmit and receive Group 3 facsimiles at rates of up to 14,400 b/s.

## Supported Features

NaturalFax supports the following features:

- Enhanced Group 3 fax features such as:

- 1D, 2D, and MMR
  encoding

- Error correction mode (ECM)

- Low, high, and superhigh resolutions

- Standard page width formats

- The T.37 format, specified as 1D encoding, low resolution, and A4 page width

- The ability to convert documents into different formats, resolutions, or encodings online (on-the-fly) or offline

- The ability to poll a remote fax terminal and request that it transmit a fax.

For more information, refer to Fax protocols and Group 3 protocol.

## NaturalFax and NMS hardware

NaturalFax runs on NMS hardware. This hardware consists of various telecommunications interfaces, high-speed controllers, and arrays of DSPs.

On AG and CG boards, the fax modems run on TI C5x and C54x DSPs, sharing them with other telephony algorithms such as voice record and play. The T.30 fax communication protocol runs on the AG or CG board controller and host processor. This sharing of DSP and controller resources contrasts with traditional chip-per-port designs, and provides the highest density and lowest cost-per-port fax boards and systems.

For QX 2000 boards, NaturalFax runs on the TI C549 DSP, which serves both as a DSP resource and board controller. The simplified architecture of the four port QX design leads to high performance at a low cost.