A first datum of a message is communicated from a first computing device to a second computing device with encryption of the first datum. A second datum of the message is communicated from the first computing device to the second computing device without encryption of the second datum. In one example, the second computing device communicates information to the first computing device responsive to a request from the first computing device to the second computing device. The information includes a procedure that causes the first computing device to select the first datum for encrypted communication to the second computing device and select the second datum for non-encrypted communication to the second computing device.