Nowadays, many applications require security of information communicated between parties that may exist in different countries or continents. The fact that the key establishment messages will traverse such long distances over a network that may be insecure raises many concerns related to the communication, computation, storage, reliability and security of the establishment process. Even though different key management protocols have been proposed, we show that there are several aspects that threaten their scalability, reliability, or security. In this paper, we propose a novel 3-layer protocol for key management in global-scale applications, and show that it provides better scalability and reliability and less vulnerability to security threats than the existing protocols.