Anonymous communication in MANET´s, solutions and challenges

A mobile ad hoc network (MANET) is designed for small groups of people with same special interests who want to communicate through their available devices like laptops or cell phones to share their ideas easily, quickly, and with minimum requirements. However providing a secure communication platform for this kind of network is a challenge because of the shared wireless medium. In MANET there is no fixed infrastructure like routers in wired network or an access point in managed wireless network to relay packets between nodes. Instead, each node participates in routing by forwarding data for other nodes. MANET has become popular in several application areas, including when a group of soldiers in enemy territory need to communicate through their available devices to receive a command or report their situations. The content of messages can be secured with cryptography, but vital information like nodes´ identities and their locations can be revealed by traffic analysis. In most of these applications security is very important however each of them needs a different level of security. In conclusion, in the routing process, using pseudonyms instead of real identities helps to hide real identities. Pseudonyms have to be changed dynamically since traffic analysis uses the same mechanism to analyze real identifiers and pseudonyms. In addition, critical data that reveals information to attacker has to be encrypted. Having too much encryption/decryption is not efficient and creates a big overhead for the nodes that have restricted computing power. To avoid information deduction we need to keep the message size unchanged. Consequently it is better not to add routing information to RREQ message otherwise we have to pad messages to make them the same size, adding extra overheads. The last word is how to break up an anonymous communication. Since the purpose is security and privacy not ambiguous communication, everyone should not be capable of setting up an anonymous MANET.