SBD can listen on any port you like. If you don't specify a port it will default to port 31415. The transport protocol is SBD, which is based on a one-time pad symmetric key and a keyed-hash message authentication code (HMAC), which verify data integrity and the authenticity of a message. The client and server need to have the same key in order for system to accept remote commands. The keys are nothing but two identical files with randomly generated characters that you need to create only once and keep them secret.
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