Key distribution in a wireless system

#This application was originally filed as PCT Application No. PCT/IB2014/058998 filed Feb. 14, 2014.

#This disclosure relates to wireless communications and more particularly to key distribution in a system comprising at least one mobile device.

#Mobile devices can be used for wireless communication and various computing tasks. For example, use of mobile devices with wireless connectivity such laptops, tablets, smart mobile phones and so on is well established. Wireless communications can be provided between mobile user devices and access points such as base stations, servers, machine type devices and so on. Communications can also be provided between mobile devices.

#Embodiments will now be described in further detail, by way of example only, with reference to the following examples and accompanying drawings, in which:

#FIG. 1 shows a schematic diagram of two devices in communications in accordance with an embodiment;

#FIG. 2 shows an example of an acceptance interval of a rotation angle for key distribution;

#In the following certain exemplifying embodiments are explained in the context of wireless or mobile communications where secure communications are provided for communicating devices where at least one of the devices is a mobile communication device. A mobile device of a user for communications is often referred to as user equipment (UE) or mobile terminal. A mobile device may be provided by any device capable of sending wireless signals to and/or receiving wireless signals on a wireless channel. The mobile device is also provided with apparatus for communication on an optical channel. Non-limiting examples of mobile devices include a mobile station (MS) such as a mobile phone or what is known as a ‘smart phone’, a portable computer such as a laptop, tablet or a personal data assistant (PDA) provided with wireless communication capabilities, or any combinations of these or the like. An appropriate mobile device is provided with at least one data processing entity, at least one memory, and other possible components for use in software and hardware aided execution of tasks it is designed to perform, including control of communications with other parties and features relating to secure communications. The data processing, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets.

#Quantum key distribution (QKD) can be used for securing the communications. Cryptographic schemes that use properties of quantum mechanical systems to distribute a secure key are considered as providing high levels of security. For example, the current thinking is that even a powerful eavesdropper who would only be limited by the laws of physics should not be able to compromise the security of the scheme. Implementations of quantum key distribution schemes rely on sending single photons between two terminals.

#An example of a possible use of QKD is where a handheld mobile device establishes a shared key with a stationary terminal. It is also possible that both of the terminals are mobile. Other types of quantum key distribution systems, for example those for satellite/airplane/balloon to ground communications are also possible.