-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Aloha!
Hilarie Orman wrote: > An ARM is far too much hardware to throw at "read sensor/munge > data/send data". No, they are not. The Cortex M0+ is aimed at these kinds of very simple systems that runs for many years on a single battery. Look at the STM32L0 series from ST for example. These devices can run on energy harvesting and very tiny physically and very, very cheap (ten-ish cents in high volume): http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus/stm32l0-series.html?querycriteria=productId=SS1817 The STM32L021 has an AES-128 core. Not very fast (200+ cycles), but several times faster than SW. You can also run the AES core wile the CPU core is in power save mode. Another example is the Zero Gecko from Silicon Labs. Same price range, a huge number of power modes. And an AES core that is really fast. 50+ cycles for AES-128, which basically means 4 cycles/round (which implies 4 S-boxes) https://www.silabs.com/products/mcu/32-bit/efm32-zero-gecko/pages/efm32-zero-gecko.aspx Pre-shared key is whats easiest. But I've implemented Curve25519 for key exchange on the STM32 device and can achieve <1 sec performance with about 1 kByte RAM and 8 kByte code. I'm sure Peter Schwabe has some much better results. Yes, you can limit yourself to an 8-bit MCU and shave off some cents and a little bit of power. But for most applications I see, a Cortex M0+ meets technical and commercial requirements too. - -- Med vänlig hälsning, Yours Joachim Strömbergson - Alltid i harmonisk svängning. ======================================================================== Joachim Strömbergson Secworks AB joac...@secworks.se ======================================================================== -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBCAAGBQJXx923AAoJEF3cfFQkIuyN4tkP+QGscSmBzUAPbamlaRqpm7sh zVwhMwhllJMdTs+HozeSbMvtw7JlO5vu+PyD/El4sxP2SAQhv1LqJFaC0nxuCJ2P I+RxISEkrxYYB2YDRGlPd3Cfm4cRrDBd/BQCPMZuAQurWxH7ptMMKIZ3hS6NuOIb gyluKMDMrUW9qFx0lrpa3yAMPHrBqlhHl1GmcUMJwoRVGOxDdc243YjNB7J/FEDh pJCzI8Dv4uyWEufr0cBv1xCiSY4eaalv25H/Cyc3rZ78Os7d52DUyuBD8IAuAkkH i32L2gK7CbrCF/3zw+Tv2aDn1ncGOiucENmQIzO99hwWwtJFC7TN59rCtoArmh5U EC0Ncq1IIbicrot+DLibHNvSWk0c15bvtg1c06UecME21SF2t8ZigF0OuYKGdeu1 a4h0dUcNUyQxUbAs9JDTXtwABvR7CMNZi3kD5Vh8NfvK7DmojPVThrQ1r/2x+6hS QnPiZcuvedjkM19y1hRchZQT23qPJQ4TrC5MvQSHnU20oW3QomPJfTAXtCctsN5s 3b+ZdWh5/EAysPpgjzzwKP0mWN3tkeSKROsh6BabMku84zerKPzCn5MwhyhUqHLD Sv453a5oK0ne5pD/b7CIPWRwK2Z6/6pFN+jWPG0SZtZTgEJjkSVPaskMd51SVSga EkqJv7VnqIa5lP5es+Is =ri48 -----END PGP SIGNATURE----- _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
