Omni 56K Plus Series User’s Guide

Before the security type or level can be changed, the modem requires the supervisor password.

For type2 security, the remote site will be prompted to enter the user password. A maximum of 3 tries in 40 seconds is allowed. If a correct password is not entered within this time limit, the line will be disconnected. If the remote site is to enter the call-back number, it will be prompted to do so.

2.6Fax function

2.6.1 Fax Physical Layer Protocol

Table 2-6 Fax Physical Layer Capacity

STANDARD

BIT RATE [BPS]

BAUD RATE [BAUD]

MODULATION

CARRIER FREQUENCY [HZ]

 

 

 

 

 

V.17

14400-7200

2400

TCM

1800

 

 

 

 

 

V.29

9600-4800

2400

QAM/DPSK

1700

 

 

 

 

 

V.27ter

4800-2400

1600/1200

PSK/DPSK

1800

 

 

 

 

 

V.21

300

300

FSK

 

 

 

 

 

 

2.6.2EIA Class 1/Class 2/Class 2.0 Command Set

Please refer to Fax Command Set in Chapter 4.

2.6.3ITU-T T.30 Fax Protocol

The ITU-T T.30 fax protocol is known as the G3 fax handshake signals and procedures. The modem takes full control of this protocol - initiating and terminating fax calls, managing the communication session, and transporting the image data. Therefore, the modem relieves the computer fax software of the T.30 protocol handling.

You modem allows for fax speeds up to 14400 bps when transmitting to a fax machine which complies with the V.17 fax standard. Speeds will fall back to 12000, 9600, or 7200 bps in poor line conditions. When connecting to a G3 fax device, your modem allows for fax speeds up to 9600 bps and will automatically fall back to 7200, 4800, and 2400 bps if the line quality is poor.

2.7Voice Function

Voice capability stands for the modem’s ability to digitize incoming voice messages, which the computer stores and forwards. It also means that the modem can playback the recorded digitized voice on line for a message announcement.

2.7.1 Voice IS-101 Command Set

Please refer to the Voice command sets in Chapter 4.

2.7.2 4-bit Voice Data Compression

The main issue in the digitized voice mode is the amount of storage required. A relatively simple ADPCM algorithm can reduce the speech data rate to half the rate and maintain about the same voice

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Specifications and Function Description