How to use Public Infrastructure for Secure Communications

Transcription

1 How to use Public Infrastructure for Secure Communications How to use Public Infrastructure for Secure Communications White Paper October 2014 Page 1 of 7

2 How to use Public Infrastructure for Secure Communications CONTENT Page No. Secure Communications over a Public Infrastructure... 3 Introduction... 3 Existing communication approaches... 3 The limitations of existing approaches... 4 The opportunity from mobile networks... 4 How can we secure public networks?... 5 Moving forward... 5 Page 2 of 7

3 How to use Public Infrastructure for Secure Communications Secure Communications over a Public Infrastructure The future of RF radio communications and the growing use of public infrastructure for enabling longer range secure communications. Introduction There are many communication options from simple Walkie Talkies to Private Mobile radio (PMR) trunked networks and Cellular Mobile phones. Every option has its own characteristics in terms of coverage, infrastructure, closed or open network, and cost. Mobile networks offer by far the best coverage, but they fall short of the security requirements of organisations like the police, private security and military. Private networks offer this security but lack the coverage of mobile networks. Most communication networks are a compromise between the two. This whitepaper will explain the strengths and weaknesses of each of the existing communication approaches, and outline how a new generation of devices could communicate securely over mobile networks. Existing communication approaches Walkie Talkie Walkie-Talkies are easy to use and require no infrastructure, however with no infrastructure the range is limited. Range can be improved using simple relays or with a gateway into other communication systems. The typical users are teams that work in close proximity and don t have access to infrastructure, can t rely on infrastructure or don t want the cost of using infrastructure - either the capital cost of setting up a private network or the ongoing cost when using a commercial network. Page 3 of 7

4 How to use Public Infrastructure for Secure Communications Trunked PMR (private network) Trunked PMR networks provide reliable coverage in a specific geographical area. The network requires specialist infrastructure to be deployed which has limited mobility. Coverage is provided in a local area but can be extended using gateways into fixed telecom infrastructure. Typically the network infrastructure is restricted to the intended users, usually teams that work in a constrained geographical location such as a stadium or industrial site, or a number of sites in relatively close proximity. Cellular Network (public network) Cellular networks provide extensive coverage (effectively worldwide) although there are areas of limited coverage in rural areas, inside large buildings or subsurface. The infrastructure setup costs are significant, usually undertaken by a large private venture and the recovery model relies on subscribers paying for the service when they use it. Typical users are public and commercial organisations. Communications are usually not sensitive so while there is some level of security, it is not at a level that police or private security companies would require. The limitations of existing approaches The key disadvantage of radio communications is the range of a radio signal. Even the most powerful radio transmitters are only capable of reaching a limited geographical region. New technology such as networking can improve the local RF range providing multiple communications paths between radios and increasing the range without the need for a pre-deployed repeater infrastructure. Mobile networks on the other hand are near universal but lack the security of controlled private networks. Each approach to mobile communications has its benefits and drawbacks so it is increasingly common to see a combination of approaches to provide an optimum solution. The opportunity from mobile networks The growth of commercial mobile phone networks provides a worldwide communications platform. The evolution of the mobile phone network toward more data services, in particular, the growth of low cost Voice Over Internet Protocol (VOIP) services is forecast to continue as the high-speed Long term Evolution (LTE) rollout gathers momentum and network access becomes even more commonplace. Mobile networks offer more or less universal reception. Page 4 of 7

5 How to use Public Infrastructure for Secure Communications Private radios which can tap into the mobile network could therefore communicate with each other regardless of distance and with no need to set up specialist infrastructure. Using these networks for secure communications has been resisted because of security concerns. However modern encryption techniques make such concerns unnecessary. It is therefore time to take advantage of public networks to combine range with security. How can we secure public networks? Taking advantage of these developments in public networks is remarkably simple, if radios which encrypt voice data before transmission are used. Modern encryption technology makes encrypting and decrypting voice data to secure it over a public network simple in much the same way that s can be secured over the internet by encrypting them between the sender and recipient. Encryption should be to a recognised international standard such as The Advanced Encryption Standard AES, the standard used by the US government. This will ensure voice data is secure until it is received by the intended recipient. With encryption built into the radio, voice data can be secured end-to-end, whether it is transmitted RF radio to radio, or it is carried over a public infrastructure. When radios are in RF range, RF communication is used and encryption ensures that their communication is secure. When a public infrastructure is needed to extend coverage, the radios can link to an IP network such as LTE, 3G or Wi-Fi. Voice data is encrypted by the radio prior to being sent to the IP network, and is decrypted by other radios connected to the IP network once received, thus ensuring it is secured end-toend. Moving forward Trunked PMR networks are often gatewayed to cellular or fixed infrastructure such as IP networks to extend the local PMR communications worldwide. Smarter radio devices can now do this internally, removing the need for extra networks and infrastructure required for Trunked PMR. Going forward, secure communication devices will utilise other communication systems. Secure encryption can be handled by the device and range can be achieved using networking or local infrastructure. True, reliable global reach, never really available to the RF radio user, can be realised by enabling these smart radios to link into an IP gateway and take advantage of VOIP services for global coverage. In addition these smarter radios can carry their own Page 5 of 7

6 How to use Public Infrastructure for Secure Communications encryption to provide end to end encryption even when communications is over public networks as it is passed as a digital data stream. This move forward, long possible but only recently implemented into practical system, has significant implications for the future of secure communications. Page 6 of 7

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