There are two sites. One is the front end and other is the backend. Both are on two separate physical networks. Front end has a database and backend has its own database and the data needs to be shared between each other on daily basis/batch process. The Backend database holds highly classified information and therefore, one of the mandatory requirement for backend connectivity is that the data should not be exchanged over a 'wired' network at all i.e. both the networks should not be connected by any means. So thinking out of blue to fulfill this requirement below are the few options I could come up with.
1. Connect the front end and back end database over the wire through a switch. Connect another switch to the second NIC of backend database. Control both the switches via 'Remote Reboot Unit / Remote Power Control'. During the data transfer between the databases, power down the second switch through power control appliance. When the data transfer is over, power down (through power control appliance) the first switch and power up the second switch for backend communications
2. Same as option # 1 but use the time-based ACL on Layer 3 switches instead for complete traffic blocking (More of a logical disconnect but not really physical)
3. Some kind of a Robotic media handler. Media could be USB, CD or Tape. The robot would unload the media from library one (which holds front end database snapshot) and load it into the library two (to upload the data into the backend database). Both the networks are physically separate. Yet to find one robotic device as such.
4. Network Switch Circuit Breaker: Both the databases are connected via a switch. The internal circuitry of the switch is 'adjustable'. That is, once the data is transfered, the internal circuitry of the backend database port is switched to another port on the switch (i.e. breaks the complete connection with the front end database). Well, never heard of such a thing. Just thinking big.....(Like the oldest telephone networks wherein for every call the lines would be manually patched by the operator. Also could be a switch box with a big button on it. For e.g. button position 1 means allow traffic, button position 2 means block traffic.
Please suggest if anyone has tried out something like that and it has worked in Production environment.
The bottom-line is both the networks should not be connected and the data needs to be exchanged between both the networks. An automated solution is required and not manual (such as a human manually shifting CD's every night).
Looking forward to your bright ideas.