A mesh device for receiving and processing a private beacon message, which can be represented by one or more Bluetooth Low Energy mesh packets. Upon receiving the private beacon message, the mesh device decrypts a first portion of the private beacon by using a first encryption key corresponding to a first subnet, wherein the first portion comprises an initialization vector (IV), in the form of an index or other indicator. The decrypting using the first encryption key results in a first decrypted value for the IV index. The mesh device then determines whether the first decrypted value for the IV index is valid or invalid. If the mesh device determines the first decrypted value to be valid, the mesh device proceeds with authenticating the data contained in the private beacon message.