Overhead is negligible because military would use symmetric cryptography. Message authentication code can be N bits for 2^-n chance of forgery. 48-96 bits is likely sweet spot and barely doubles size for even tiny messages.
Elliptic curve crypto is there if for some reason key distribution is a terrible burden. typical ECC signatures are 64 bytes (512 bits) but 48 bytes is easy and 32 bytes possible with pairing based ECC. If signature size is an issue, use asymmetric crypto to negotiate a symmetric key then use symmetric crypto for further messages with tight timing limits.
Overhead is negligible because military would use symmetric cryptography. Message authentication code can be N bits for 2^-n chance of forgery. 48-96 bits is likely sweet spot and barely doubles size for even tiny messages.
Elliptic curve crypto is there if for some reason key distribution is a terrible burden. typical ECC signatures are 64 bytes (512 bits) but 48 bytes is easy and 32 bytes possible with pairing based ECC. If signature size is an issue, use asymmetric crypto to negotiate a symmetric key then use symmetric crypto for further messages with tight timing limits.