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Public key cryptographic primitive (e.g., the famous Diffie-Hellman key agreement, or public key encryption) has recently been used as a standard building block in authenticated key agreement (AKA) constructions for wireless sensor networks (WSNs) to provide perfect forward secrecy (PFS), where the expensive cryptographic operation (i.e., exponentiation calculation) is involved. However, realizing such complex computation on resource-constrained wireless sensors is inefficient and even impossible on some devices. In this work, we introduce a new AKA scheme with PFS for WSNs without using any public key cryptographic primitive. To achieve PFS, we rely on a new dynamic one-time authentication credential that is regularly updated in each session. In particular, each value of the authentication credential is wisely associated with at most one session key that enables us to fulfill the security goal of PFS. Furthermore, the proposed scheme enables the principals to identify whether they have been impersonated previously. We highlight that our scheme can be very efficiently implemented on sensors since only hash function and XOR operation are required.

Information Centric Networking (ICN) is a promising future networking architecture, and Named Data Networking (NDN) is considered to be its authoritative and representative scheme. In recent years, applying ICN/NDN concept in Mobile Ad-hoc Network (MANET), i.e. Name Data Mobile Ad-hoc Network (NDMANET), becomes a research hotspot. Compared with traditional IP protocol, NDN scheme is thought to be more robust and profitable to the node mobility and dynamically changed topologies in MANET. This paper focuses on NDMANET’s in-networking caching strategy, which provides a great flexibility and efficiency for data dissemination and is a vital feature of NDMANET. Firstly, the paper investigates and analyzes some existing caching strategies which are widely applied in the ICN/NDN domain. On that basis, a novel Content Popularity and Distance based Interval (CPDI) caching strategy is derived for NDMANET, with the purpose of improving its network performance. Comprehensive simulation experiments have been carried out and the results illustrate that the proposed CPDI caching strategy can introduce considerable improvements on the average cache hit ratio, the average number of cached data packets, and the average energy consumption with only slightly degrading the average download delay.

In this study, a novel aluminum phosphate (AlPO4) heat-resistant layer reinforced with aluminum silicate fiber (ASF) was successfully compounded on a poly(ether sulfone) (PES) matrix via the preparation process of high-temperature heat treatment and vacuum hot-pressing sintering technique. The influence of the ASF content on the morphology, thermal, mechanical, and dielectric properties of the as-fabricated aluminum silicate fiber reinforced aluminum phosphate–poly(ether sulfone) (ASF/AlPO4–PES) layered composite was investigated. The results reveal that the incorporation of aluminum silicate fiber/aluminum phosphate (ASF/AlPO4) heat-resistant layer can significantly improve the thermal stability and mechanical performances of the PES matrix composites. Compared with the pristine PES, the ASF/AlPO4–PES layered composite containing 8.0 wt % ASF exhibited better high-temperature resistance properties (300 °C) and a lower thermal conductivity (0.16 W m−1 K−1). Furthermore, the dielectric constant and dielectric loss tangent of this PES matrix composite decreased to 2.16 and 0.007, respectively. Meanwhile, the frequency stability of the dielectric properties for the ASF/AlPO4–PES layered composites was remarkably enhanced with increasing ASF addition at frequencies ranging from 102 Hz to 5 MHz. This was attributed to the existence of microscopic pores within the ASF/AlPO4 layer and the strong interfacial bonding between the ASF/AlPO4 layer and the PES matrix. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45542.