Ludwig: > On Wed, 2013-05-29 at 16:34 -0700, Jim Schaad wrote: >> <chair> >> > >> Method #1 >> >> Key Agreement Secret --(KDF)--> Key Encryption Key --(Key Wrap)--> Content >> Encryption Key >> >> Method #2 >> >> Key Agreement Secret --(KDF)--> Content Encryption Key. >> >> [...] question: >> >> I have a use case where doing Method #2 is the correct method or a much >> better method. If this is a true statement, please provide the use case to >> use. > > I think I have a use case where method #2 is better. I'm working on > processing JWE objects on constrained devices and transferring them over > low capacity networks. If my understanding of method #2 is correct, it > would leave the JWE Encrypted Key empty, thus reducing the size of the > JWE message. > I therefore think method #2 is preferable for this use case, since it > saves both bandwidth and RAM on the constrained device.
Is this always a pairwise communication? If the message is ever intended to be decrypted by two or more parties, then you need Method #1. If there are every instances of more than one recipient, then you need to have the code and memory for Method #1 anyway. And, as Richard already pointed out, it is not a lot of memory. Russ _______________________________________________ jose mailing list [email protected] https://www.ietf.org/mailman/listinfo/jose
