How to protect data on your hard disk if it is in an unfriendly environment?
The essence of the problem as follows. There is a server located on the side of our company. There is a hardware client module, which is in a public place, communicate with the server via a secure protocol. The client module contains the key, with which it is authenticated on the server. Need to make sure that the key could not get into the wrong hands, in case of theft of client module. Obligatory condition of the problem is the absence of agents that could be transferred to a secret PIN number, which would have to be administered, for example, to connect the encrypted volume when module is booting.

Does anyone have any ideas how this can be done?
How to protect data on your hard disk if it is in an unfriendly environment?
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The essence of the problem as follows. There is a server located on the side of our company. There is a hardware client module, which is in a public place, communicate with the server via a secure protocol. The client module contains the key, with which it is authenticated on the server. Need to make sure that the key could not get into the wrong hands, in case of theft of client module. Obligatory condition of the problem is the absence of agents that could be transferred to a secret PIN number, which would have to be administered, for example, to connect the encrypted volume when module is booting.

Does anyone have any ideas how this can be done?