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Security Systems, uWSGI H2 (NPN, ALPN), SFTP Integration, SQLite3, Ubuntu, Sarmat

posted Jun 11, 2016, 11:38 PM by Sami Lehtinen   [ updated Jun 11, 2016, 11:38 PM ]
  • Had a new home security system installed, this is really awesome: Featuring: 24/7 remote video monitoring, remote video storage for a few days, radar (microwave) motion detection complemented with video (with IR) motion detection, backup data channel (cutting all external wiring won't help), extended battery backup, door and window sensors, fire monitoring, leak monitoring, alarm button, secure wireless cryptographic arm / disarm tags, low / high temperature alarm, mobile monitoring / activation, direct video / audio channel to response center. I think this is pretty neat solution compared to the traditional passive infrared / send a guard option. False alarms do not require guard visit, as well as there's a video record of people entering and leaving the premises, etc. - Earlier when we played with different security systems, the Doppler RADAR motion detection unit was the hardest one to evade, it was practically impossible. Evading Passive Infrared (PIR) wasn't that hard, if you just knew where the sensors where and used suitable gear and there wasn't any major background ambient temperature differences. Using a thin aluminium thermal foil is enough. Anyway, that's something which would naturally trigger video motion detection. Night / Stay mode which keeps electronic perimeter fence enabled, but disables selected cameras and motion detectors, etc. Duress code feature. Mobile app for real time video monitoring and alerts, etc. So many systems I've seen are technically out dated, but this one is really neat
  • Played bit more with uWSGI it seems that the version doesn't actually support HTTP/2 it actually supports spdy/3 and Next Protocol Negotiation extension  (NPN) but not Application-Layer Protocol Negotiation (ALPN). - This means that the current 'protocol support' is slightly out of date. Let's see if this gets fixed soon enough.
  • Uah, integrations which require every integrated system to run separate independent SFTP server. What an perfect way to integrate systems nowadays. Yeah, sure. No problem, but still annoying. - Done
  • Read FAQs and project descriptions of Apache Spark and Apache Flink. As well as corresponding Wikipedia articles: Spark, Flink.
  • Had a few interesting discussions with one DBA. He was surprised by my blog post where I wrote about query performance on local data using a large number of simple queries. Basically corresponding to key value lookups. They ended up using SQLite3, interestingly. I know there are even faster key value storages, but SQLite3 gives you nice standard solution and you can fine tune it using a few PRAGMA statements. The most important thing that allowed them to use SQLite3 was the fact that they didn't have multiple parallel writes. Which naturally won't work with SQLite3. Subsequent writes can be quick, but long write transactions will kill it. Then your system is toasted.
  • Ubuntu 16.04 dropping Upstart. I remember what kind of mess it was when Upstart came and I made a distribution upgrade. Let's hope it isn't that bad again. Everything got more or less broken. Ended up reinstalling the system.
  • Checked out the new heavy nuclear missile from Russia RS-28_Sarmat aka Satan II.