Insys GPRS 5.0 serial 11-02-01-03-10.014 Manuale Utente

INSYS GPRS 5.0 serial 

 

Information Regarding GPRS 

 

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The IP address of the GPRS end device is dynamically allocated by the provider and is 
temporary, i.e. during the next dialup at the provider a new IP address is allocated. 
 
In almost all GPRS networks the IP address can not be accessed from outside (routing-
enabled), as the providers perform the addressing for the switch from GPRS networks to 
the “normal Internet” via a NAT table (Network Address Translation) to manage the ad-
dress area limited by IPV4. 
 
Furthermore, firewalls offer a security aspect, so the GPRS device is not accessible by so-
called scanners because the IP address can not be accessed. As GPRS is billed by the 
amount of data, this prevents unauthorized data traffic.  
 
This also means that the following functions may not be possible: 

¾

  Pinging the GPRS device from outside 

¾

  Establishing TCP/IP connections to the GPRS device from outside 

¾

  Sending UDP/IP packets to the GPRS device from outside 

 
All connections (channels) must be opened starting with the GPRS device. This means 
that the GPRS device or the application behind it can only react as CLIENT. 
 
Exceptions to this restriction will be provided by the according provider, if available. 
Please also contact your provider to clarify if it is possible to use a VPN (Virtual Private 
Network) for possibly required server functionality.