Future 5G networks must provide communication services to a great and heterogeneous collection of scenarios: from traditional mobile communications to emerging applications such as Industry 4.0 or the Internet of Things (IoT). In this context, the network slicing technique is defined, where network resources are packaged and assigned in an isolated manner to the sets of users according to their specific requirements. Two different domains are, thus, defined: the intra-slice domain (where dedicated and specific solutions have to be deployed) and the inter-slice domain (including transversal solutions). One of the key topics which should be redefined following this approach is security. Traditionally, some solutions (such as stream ciphers) were not considered in mobile networks. However, 5G systems will be extensively employed in other new and very distinct scenarios, where requirements are different. For example, the use of resource constrained devices with little mobility and real-time data streaming in certain IoT applications suggests the use of stream ciphers (and other similar techniques) as the main security solutions. Therefore, in this paper, we investigate and propose a new security solution for emerging 5G networks, to be applied in the intra-slice domain. The proposed solutions employ lightweight pseudo-random number generators in order to provide the keystream used in stream ciphers which protect the private information and hide the communication signals in the frequency spectrum using spread spectrum techniques. We also describe and evaluate a first implementation of the proposed solution, using both, a simulation scenario and a real deployment.
Ministry of Economy and Competitiveness through SEMOLA project (Grant Number: TEC2015-68284-R) Autonomous Region of Madrid through MOSI-AGIL-CM project (co-funded by EU Structural Funds FSE and FEDER) (Grant Number: P2013/ICE-3019) Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación, Fondo Europeo de Desarrollo Regional through the COPCIS project (Grant Number: TIN2017-84844-C2-1-R), Ministry of Education through the FPU Program (Grant Number: FPU15/03977)