1. IoT
   1. interconnection
      1. of
         1. Uniquely identifiable
            1. embedded-devices
            2. within
            3. the Internet
   2. objects
      1. will have to
         1. use
            1. IPv6
      2. sensors
      3. actuators
   3. will
      1. require
         1. low-power
            1. data
            2. radios
            3. for connection to
            4. the Internet
2. Oscillators
3. Ethernet
   1. Definitions
      1. MAC
         1. Media access control. This is the part of the system which converts a packet from the OS into a stream of bytes to be put on the wire (or fibre). Often interfaces to the host processor over something like PCI Express (for example).
      2. PHY
         1. physical layer - converts a stream of bytes from the MAC into signals on one or more wires or fibres.
      3. MII
         1. Media Independent Interface. Just a standard set of pins between the MAC and the PHY, so that the MAC doesn't have to know or care what the physical medium is, and the PHY doesn't have to know or care how the host processor interface looks.
         2. Management Signals
            1. MDIO
            2. Management data IO line (bi-directional)
            3. MDC
            4. Management data clock line (uni-directional for MII)
   2. Subtopic 2
4. Satellite Navigation
   1. Transit
      1. Navy
      2. mid 1960s
         1. to
            1. 1996
      3. purpose
         1. provision of navigation data for Polaris missile submarines
      4. satellites
         1. six
         2. orbits
            1. nearly
            2. circular
            3. polar
         3. altitudes
            1. 1075kKm
         4. period of rev
            1. 107 minutes
   2. GNSS
      1. Receiver
         1. messages
            1. types
            2. GGA
            3. GPS Fix data
            4. which provides
            5. 3D Location Data
            6. Accuracy Data
            7. GSA
            8. Nature of fix
            9. no fix
            10. 2D
            11. 3D
            12. PRNs of Sats (and hence their number) used in the current solution
            13. DOP
            14. Dilution of precision
            15. smaller the better
            16. 1.0 for 3D fix
            17. GSV
            18. Satellites in view
            19. PRNs of the Sats in view
            20. Eelevation angle of each sat
            21. Azimuth angle of each sat
            22. SNR (0 to 99 dB)
            23. more
            24. GLL
            25. Geographical Pos. Lat/Long
            26. RMC
            27. Recommended minimum specific GNSS data
            28. Position, velocity and time
            29. VTG
            30. Course over Ground and Ground Speed, horizontal course and horizontal velocity
            31. ZDA
            32. Time & Date
            33. standardized
            34. by
            35. NMEA
            36. for
            37. GNSS
            38. GPS
            39. LORAN
            40. Omega
            41. Transit
            42. 8-bit ASCII data
            43. 1 start bit
            44. 1 stop bit
            45. No parity
            46. max characters=79
            47. excluding
            48. $
            49. <CR>
            50. <LF>
         2. interface
            1. TTL
            2. RS232
         3. Baud-rate
            1. upto
            2. 115200 bps
      2. Spoofing
         1. A GPS spoofing attack attempts to deceive a GPS receiver by broadcasting counterfeit GPS signals, structured to resemble a set of normal GPS signals, or by rebroadcasting genuine signals captured elsewhere or at a different time.
            1. Examples
            2. One common form of a GPS spoofing attack, commonly termed a carry-off attack begins by broadcasting signals synchronized with the genuine signals observed by the target receiver. The power of the counterfeit signals is then gradually increased and drawn away from the genuine signals.
            3. It has been suggested that the capture of a Lockheed RQ-170 drone aircraft in northeastern Iran in December, 2011, was the result of such an attack
5. BDD
   1. A specialised form of Hoare logic applied to TDD.
   2. Specifies that test of any unit of SW should be described in terms of the desired behaviour (i.e. requirements set by the business) of the unit.
   3. BDD is an “outside-in” methodology. It starts at the outside by identifying business outcomes, and then drills down into the feature set that will achieve those outcomes. Each feature is captured as a “story”, which defines the scope of the feature along with its acceptance criteria.
   4. Provides SW developers and management teams with shared tools and shared process to collaborate on SW development.
   5. Reference
      1. Hoare Logic
         1. Hoare triple
            1. {P} C {Q}
            2. When precondition P is met executing the command C establishes the postcondition P
      2. Useful link
6. Geo fencing
   1. Geo-fencing (geofencing) is a feature in a software that uses GPS or RFID to define geographical boundaries. A geofence is a virtual barrier. "jailbroken" refers to breaking Apple's software lock that prevents you installing (potentially nefarious) third party applications. Several of these applications "GPSCheat, LocationFaker etc." are able to intercept the data from the internal GPS receiver (high level information like NMEA data, not raw satellites) and change the location to a user supplied one before passing it on to other applications. This doesn't affect how the GPS actually works, it's just a change in the API internally in software. The people in the discussion seem to be trying to get access to online TV streaming applications that aren't available in their area, like someone in France trying to watch BBC iPlayer, this is not allowed because of the way the TV programs are funded so the app asks the operating system where in the world it is before running. A process known as "geo-fencing".
7. ANPR
   1. Uses
      1. Optical character recognition
         1. to identify number plates
   2. restricts
      1. visible light
   3. camera has an IR light source
   4. Number plate reflects light back to the source due to loads of small hemispheres on it. e.g. high visibility clothing.
   5. The only light ANPR camera sees is the IR reflected from number plate.
8. Timing protocols
   1. NTP
      1. used on
         1. Internet
      2. accurate
         1. few milliseconds
      3. spatial extent
         1. WAN
      4. built on
         1. UDP/IP
            1. UDP port 123
      5. hierarchy
         1. top
            1. UTC
         2. Stratum 1
            1. direct
            2. access
            3. UTC source. e.g. GPS
         3. stratum 2
            1. syncs with
            2. Stratum 1
         4. and so on
   2. PTP
      1. provides
         1. synchronisation
            1. phase
            2. frequency
            3. time of day
         2. over
            1. packet based networks
            2. LAN
      2. timestamps
         1. software
         2. hardware
      3. accurate
         1. sub-microsecond
      4. spatial extent
         1. a few subnets
9. Carrier aggregation
   1. Combining parallel transmission paths to achieve a higher total throughput.
10. Video
    1. Analog
       1. NTSC
          1. 480i60
             1. digitized
             2. resolution
             3. max
             4. D1 (720x480)
             5. common
             6. 4CIF (702x480)
       2. PAL
          1. 576i50
             1. digitized
             2. resolution
             3. max
             4. D1 (720x576)
             5. common
             6. 4CIF (702x576)
    2. Digital
       1. VGA
          1. 640x480