ZyXEL omni.net Plus User Guide - Page 18

Omni 56K Plus Series User's Guide 2.5.6 Data Compression In the modem, the data compression is activated in an attempt to reduce the number of bits actually sent. The receiving modem applies these techniques in reverse to recover the actual data from the compressed data stream. Omni 56K Plus modems support V.44, V.42bis and MNP5 data compression protocols. Data compression needs an error-free data link to work correctly, otherwise the corrupted compressed data stream will ruin the decompression process. MNP5 is used with MNP4 error control. V.44 and V.42bis is used with V.42 error control. The compression efficiency of V.42bis is generally higher than that of MNP5. In some cases, V.42bis can be 50 % to 100% higher and in other cases it is just slightly higher. In general, it is about 50 % more efficient. 2.5.7 Repeat Dial The modem will dial the default number stored in non-volatile RAM, EEPROM , repeatedly if not connected.(s38.0=1,*Dn) 2.5.8 Cyclic Dial Dial the number stored in EEPROM at location n(0-3) if cyclic dial s44.3=1 is set. If the first dial is not successful, the modem will cycle dial through the four numbers stored in memory. 2.5.9 Caller Number Delivery (Caller ID) Caller Number Delivery (CND), commonly called Caller ID, is a new kind of phone service that may be offered by your local phone company. Check your phone company for availability. You must subscribe to it and usually pay an additional monthly service charge for this service. With CND service, the phone company's central office will send the coded caller information to the called station. This information is sent once between the first and second ring. Your modem can decode this caller information and present it to the connected computer/terminal during the second ring period as part of the call progress ring message. The modem will also report the Caller ID information if asked by the command AT*T. There are two kinds of caller information message formats sent by the phone company. One is the single message format which includes date, time, and caller ID The other is the multiple message format which also includes the caller name as registered with the phone company. The command ATS40.2=n is used to enable (n=1) or disable (n=0) the Caller ID detection function. The default is disabled. Enable it only when you have this service and want to enable its detection. The Caller ID message may cause some communication software that is not expecting it to become confused. If you plan to use the Caller ID feature, be sure you are using software that supports it. In single message format, the modem will send a ring message to the terminal as follows: RING 2-6 Specifications and Function Description