This paper presents the design and implementation of a key distribution protocol over public channels. This protocol has its own source of randomness, based on data from civil air traffic. An equivalent protocol scheme has been developed according to the theoretical protocol, “satellite scenario”. Both parties to generate symmetric keys without preshared secrets have been allowed. Keys generated in this way can be used with symmetric encryption (AES, DES). The performance of the proposed protocol has been conducted with rigorous theoretical information analysis.