Lock-Keeper: A New Implementation of Physical Separation Technology

“Physical Separation” is a simple, but hard to be realized, security concept. The paper proposes a new implementation of this principle, named Lock-Keeper. By means of the SingleGate Lock-Keeper system, which is an initial realization of the Lock-Keeper technology, the possibility of direct network attacks to a protected network can be eliminated entirely and data can be exchanged between two networks through a completely secure and reliable way. The analysis on comparing the Lock-Keeper with other similar “Physical Separation” approaches shows that this new implementation has a lot of remarkable innovations. As an advanced implementation, the DualGate Lock-Keeper is proposed by including another new “gate” unit. Along with this development, the Lock-Keeper’s performance on data transfer, especially the throughput, is improved significantly as well as some other new functional characteristics appear to make the Lock-Keeper technology more efficient, flexible and applicable. In addition, several application scenarios are revealed to explain how the Lock-Keeper can be integrated into complex structures and provide a higher level of security.