Siemens SIMATIC NET TeleControl SINAUT ST7, Системное руководство

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Installation and commissioning of the modems and routers
5.5 MD2 dedicated line modem
SINAUT ST7 station control system
System Manual, 09/2016, C79000-G8976-C178-10
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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 provider 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 some 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.
5.5 MD2 dedicated line modem
This section describes the design of the MD2 modem, its connectors, display elements and
switches.