General questions about encryption and authentication

Projects Networking, Protocols, and Devices
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I've been having problems digging up information about encryption protocols and how they are supposed to work. Typically for example, you have a key and IV and keep the key secret and make the IV known publicly to the recipient of encrypted data.

I've built a library branch (GitHub - TMRh20/nrf_to_nrf at CCMEncryption) that uses the nrf52840 CCM AES encryption module to create an encrypted & authenticated wireless radio network.

This implementation has 3 items: A key, a counter and an IV.

Right now I am generating a random IV and sending it along with each packet. Mostly just wondering if the counter value needs to be updated as well or if I can just use a static counter value.

If anybody is interested/willing to take a look here that would be great. Here is the datasheet for reference: https://infocenter.nordicsemi.com/pdf/nRF52840_PS_v1.1.pdf

The CCM data structure is described here: CCM — AES CCM mode encryption

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Found the answer, which is yes, the counter should be incremented and sent with each packet.

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