I have been looking a bit at the various block ciphers for TLS. As everyone should (pipe dream) have migrated to TLS 1.2 by now it should be considered how to prepare for TLS 1.3, when it has been implemented.
In my daily work I have been looking into which block cipher algorithms to recommend for TLS 1.2 while keeping 1.3 in mind. On Wikipedia (the treasure trove of information) I found that AES-GCM could be a good candidate for the block cipher as it will be usable for TLS 1.3 and is one of the better ciphers considering performance (see Stanford presentation on AES GCM).
This question is in part "should I use GCM or CCM", however that is - somewhat - answered here. The important part - for me - is that the cipher to be used must be possible to compute and process using a small amount of transmission data. In my context I am limited by both processing power and amount of data to be sent, so could anyone suggest or give proof of which of the block ciphers supported by TLS 1.2 and future 1.3 are best in this regard?
EDIT: To answer the comment. The clients will not be browsers as such, they will use a channel secured by TLS. The engine... I am actually not sure that is fully decided. It is going to be on machines that are set up to connect to a centralized server. I realise this sounds a lot C&C-ish, but it is more IoT-ish. I hope that answers the question and helps in giving me a hint to what the answer to my question is.