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Abstract-Cache replacement policies are developed to help insure optimal use of limited resources. Varieties of such algorithms exist with relatively few that dynamically adapt to traffic patterns. Algorithms that are tunable typically utilize offline training mechanisms or trial-and-error to determine optimal characteristics.Utilizing multiple algorithms to establish an efficient replacement policy that dynamically adapts to changes in traffic load and access patterns is a novel option that is introduced in this article. A simulation of this approach utilizing two existing, simple, and effective policies; namely, LRU and LFU was studied to assess the potential of the adaptive policy. This policy is compared and contrasted to other cache replacement policies utilizing public traffic samples mentioned in the literature as well as a synthetic model created from existing samples. Simulation results suggest that the adaptive cache replacement policy is beneficial, primarily in smaller cache sizes.

Hospitals worldwide have implemented High Frequency (HF) Radio Frequency Identification (RFID) networks for supplies tracking in ER setting, in-patient identification, surgical instrument management, and other applications. Merging of Web, Near Filed Communication (NFC), and HF RFID technologies for their combined use in e-Health applications is a logical next step due to the wide availability of NFC-enabled smartphones. This article outlines some resulting security challenges. Tags are often compliant with multiple standards that operate in the same frequency range. For example, HF RFID tags have already been adopted for in-patient tracking, yet smartphone NFC reader apps can freely access data on those tags. While tag– or session–centered security protocols exist for some RFID standards (e.g. ISO/IEC 29167), no ISO security standard is currently available for HF RFID tags. In such systems, proper traffic characterization can lead to better understanding of operation under “normal” system state conditions and could potentially help to identify security breaches.