5G networks will provide opportunities for the creation of new services, for new business models, and for new players to enter the mobile market. The networks will support efficient and cost-effective launch of a multitude of services, tailored for different vertical markets having varying service and security requirements, and involving a large number of actors. Key technology concepts are network slicing and network softwarization, including network function virtualization and software-defined networking. The presented security architecture builds upon concepts from the 3G and 4G security architectures but extends and enhances them to cover the new 5G environment. It comprises a toolbox for security relevant modeling of the systems, a set of security design principles, and a set of security functions and mechanisms to implement the security controls needed to achieve stated security objectives. In a smart city use case setting, we illustrate its utility; we examine the high-level security aspects stemming from the deployment of a large number of IoT devices and network softwarization.

Message Authentication Codes (MACs) used in today's wireless communication standards may not be able to satisfy resource limitations of simpler 5G radio types and use cases such as machine type communications. As a possible solution, we present a lightweight message authentication scheme based on the cyclic redundancy check (CRC). It has been previously shown that a CRC with an irreducible generator polynomial as the key is an -almost XOR-universal (AXU) hash function with = (m + n)/2n-1, where m is the message size and n is the CRC size. While the computation of n-bit CRCs can be efficiently implemented in hardware using linear feedback shift registers, generating random degree-n irreducible polynomials is computationally expensive for large n. We propose using a product of k irreducible polynomials whose degrees sum up to n as a generator polynomial for an n-bit CRC and show that the resulting hash functions are -AXU with = (m + n)k/2n -k. The presented message authentication scheme can be seen as providing a trade-off between security and implementation efficiency.

Random numbers are widely used in cryptographic algorithms and protocols. A faulty true random number generator (TRNG) may open a door into a system in spite of cryptographic protection. It is therefore important to design TRNGs so that they can be tested at different stages of their lifetime to assure their trustworthiness. In this paper, we propose a method for designing physical unclonable function (PUF)-based TRNGs which can be tested in-field by known answer tests. We present a prototype FPGA implementation of the proposed TRNG based on an arbiter PUF which passes all NIST 800-22 statistical tests and has the minimal entropy of 0.918 estimated according to NIST 800-90B recommendations. This is a nontrivial achievement given that arbiter PUFs are notoriously hard to place in a symmetric manner in FPGAs.

This paper presents the first results from the ongoing research project HASPOC, developing a high assurance virtualization platform for the ARMv8 CPU architecture. Formal verification at machine code level guarantees information isolation between different guest systems (e.g. OSs) running on the platform. To use the platform in networking scenarios, we allow guest systems to securely communicate with each other via platform-provided communication channels and to take exclusive control of peripherals for communication with the outside world.

The isolation is shown to be formally equivalent to that of guests executing on physically separate platforms with dedicated communication channels crossing the air-gap. Common Criteria (CC) assurance methodology is applied by preparing the CC documentation required for an EAL6 evaluation of products using the platform. Besides the hypervisor, a secure boot component is included and verified to ensure system integrity.

The number of wirelessly connected devices is expected to increase to a few tens of billions by the year 2020. Newer generations of products and applications will sharpen demands for ultra-low energy consuming wireless devices. Various techniques for energy saving based on Discontinuous Reception (DRX) are known. However, DRX is vulnerable to unauthorized or fake trigger requests by malicious adversaries aiming to drain a device's battery. Existing message authentication methods can identify spoofed messages, but they require the reception of a complete message before its authenticity can be verified. In this paper, we present a method which inserts authentication checkpoints at several positions within a message. This enables a device to identify that a message is unauthorized and turn its radio receiver off as soon as the first checkpoint fails. The presented method has a low complexity with respect to the computational and memory resources and does not slow down the receiver. It can maintain the packet format prescribed by the IEEE 802.15.4 specification, which provides for backward compatibility. Finally, it incorporates authentication checkpoints at the MAC layer, which allows nodes that do not employ the presented method to participate in the communication.