Integrator’s Reference Manual
5-34 80-99208-1 Rev. D
Accessing Packet Data Over an Asynchronous Connection
Once an asynchronous co nnection has been established for
the GSP-1620 modem, it could be used to access packet data
(using protocols such as PPP or SLIP).
If PPP is used on top of asynchronous data service, the DTE
would be assigned an IP address. PPP would be required for
Internet access using asynchronous data.
Protocols such as Z-modem or Y-modem or other proprietary
protocols could be used to transfer data between the
GSP-1620 modem and the host modem, without negotiating
PPP.
If your SCADA application requires packet data over an
asynchronous connection, here are some implementation
suggestions:
• For PPP data, contact your Service Provider to obtain
necessary account information (whatever you would
normally need for an Internet connection, such as an IP
address, DNS information, and so on).
• Set up the asynchronous connections for the GSP-1620
modem as described in Using Asynchronous Data on p age
5-30.
•Use the AT$QCPKND command with a value of 2, to allow
mixing packet data calls and asynchronous da ta calls (for
details, see Packet No Dial ($QCPKND) on page 6-50).