Titan Electronics Inc NETCOM423 Manuel D’Utilisation

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87 

NetCom 123 WLAN, 423 WLAN, 

 

This chapter documents some functions and protocols, not directly 
related to the basic function of a serial port. There is the Modem 
Emulation by IP-Modem, the Print Server mode, and the encrypted 
communication by OpenVPN™. 
The technical details of these operation modes are described in this 
separate section, because it would be to confusing to have the details in 
the description of the configuration menus. 

The Firmware version 2.0 brings the new function of IP Modem. Used 
in this mode, the serial port of the NetCom emulates a standard serial 
modem. Basically this means the NetCom will 

a)  answer to AT-commands on the serial port 
b) establish a connection to a destination 
c)  inform the connected serial device of the connection 
d)  accept a TCP connection, and inform the serial device of that 

event 

For connections the NetCom will use a TCP connection. This differs 
from a normal telephone line, so there will be some modifications in the 
behaviour. The target is an IP-Address, not a phone number. Also for 
hardware reasons the automatic baudrate detection used in today serial 
Modems is not available. However this is not a problem at all, the 
IP Modem can be installed in Windows as a Standard 33600bps 
Modem. Later there will be an INF-file for ease of installation. 

1.  The customer has a remote management installation, operating 

via telephone line. These lines may be in-house or through 
public phone systems to other destinations. The customer wants 
to reduce costs for these lines, management and possibly 
hardware, using the Intra- or Internet. 

2.  The customer wants to contact several stations from a central 

server. Because of frequent target changes he does not want to 
define the target by a Virtual Com Port. 

3. Remotely distributed devices contact a central system by 

Modem. This is the reverse of option 1.