Down the road, there will be a growing number of DApps build on Ethereum. Some of which will probably need an encrypted communication channel between their smart contracts and their use facing UI’s. If something like this already exists correct me, but a standard protocol to establish something like HTTPs (obvious called something else for Ethereum, possibly STP for secure transfer protocol) would be very useful. For instance, if a smart contract gives out unique secrete ids to its users, to be stored offline and retrieved for future use, an encrypted channel is necessary.
This EIP will build of EIP-191. Using the encryption scheme as a starting point.