Installing and putting a SINAUT modem into operation
5.4 GPRS/GSM wireless modem MD741-1
Station control system
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System Manual, 07/2009, C79000-G8976-C178-07
IP address of the partner
To allow the MD741-1 to establish a VPN connection actively, the partner must have a fixed
IP address. Many Internet Service Providers (ISPs), however, assign the IP addresses
dynamically; in other words, the IP addresses of the computers or networks with access to
the Internet change. A fixed IP address can be obtained in the following ways:
●
Fixed IP address with dedicated line to the GPRS provider
The partner is connected directly to the GPRS provider over a leased dedicated line. The
network operator then normally assigns a fixed IP address.
●
Fixed IP address from Internet Service Provider
The partner is available over the Internet and a fixed IP address has been assigned to it
by the Internet service provider. (Can be applied for from several Internet service
providers.)
●
Fixed DNS name from DynDNS service
To solve the problem of dynamic IP address assignment, DynDNS services can be used.
With such a service, the partner can be reached using a fixed domain name regardless of
its current dynamic IP address. Each time the IP address changes, the partner signals
the new IP address to the DynDNS server so that the domain name on the DNS server is
always assigned to the current IP address. Use of a DynDNS service is subject to
entering a contract with a suitable provider, for example DynDNS.org or DNS4BIZ.com.
5.4.4
Further documentation
You will find further information on the GPRS/GSM MD741-1 wireless modem on the
SIMATIC NET Manual Collection (DVD ships with every product). The separate manual on
the MD741-1 on this CD, includes among other things information on the following topics:
●
Commissioning
●
Configuration
●
Service functions
You will also find more detailed information on the GSM antenna SINAUT 794-4MR on the
SIMATIC NET Manual Collection.
