Secure communications among mobile components, like wireless sensors and RFID tags, emerge as a fundamental branch of network security, needing message confidentiality, integrity and authentication. That is: protecting the content of transmitted information, assuring that it was not altered during transmission, and proving that it was sent by an approved identified source. Object integrity is another very relevant security application. Here, the purpose is to prove that an object, having storage and transmission facilities, is not cloned. We treat the hardware implementation of security measures in mobile components while considering two major issues: Resource constraints: Such components operate under highly constrained conditions, posing a demand for minimal logic hardware while providing for approved and recognized security level. Memory security: Wireless Sensors and RFID tags are deployed in hostile environments, enhancing a need for tamper-proof storage of their secret keys. The contribution of the paper is 3-fold: - We present a novel approach to hardware minimization, serving message security while relying on approved security levels,- We show that memory security is not merely a physical problem, apparently independent of the served applications. This observation can be made general. Attention is devoted to recently announced logic gates fabrication techniques, and their relation to the devised approach, as well as their potential contribution to general security applications.