Subject: [ipwave] Protocols and Architectures for Traffic Lights

From: Alexandre Petrescu <[email-masked]>
Date: Tue, 29 Jan 2019 15:04:41 +0100

Protocols and Architectures for Traffic Lights
               Januay 29th, 2019

DIASER: a protocol used to communicate to Traffic Lights controllers.
Used in France.  Specified by AFNOR.  Closed and paying specification.
Works on hardware platforms from Lacroix (model Traffy) and Aximum
(model Maestro), and probably others.  Works on serial and on UDP/IP.
Example queries are: "DZ" to reset, "Ck" and "CJ" to query the current
color of lights, C# and CU to get the time spent in a color.

API WIM 7101, RSGC2: proprietary API interfaces used by organisation
NEAVIA of organisation Lacroix in France; it is used to provide access
to data of traffic lights controllers.  It can be used with DIASER in
a sequence way: a gateway converts from one to another.

ISO PRESTO 22951: a protocol to communicate with traffic lights
controller, to obtain priority for special vehicles.

SPAT/SSM/SRM: protocols used by future traffic lights controllers;
specified by SAE in J2735.  The 2009 version is freely available,
whereas the 2016 (non retro-compatible) is paying 100 USD,
approximative.  SPAT is Signal Phase and Timing, whereas SRM is Signal
Request Message.

SPAT-EM: an European version of SPAT, specified by ETSI, which
encapsulates SPAT.  Free access, but SPAT still paying (free
encapsulated paying).

IVERA: a protocol used in Netherlands to communicate with Traffic
Lights controllers.  Potentially VLOG is also such a protocol.

3G Segnaletica: an organisation in Italy that provides hardware for
controllers for traffic  lights.  Also has models carried in 'mobile'
traffic lights.  It provides a Raspberry Pi to access the traffic
lights data.  The Raspberry Pi uses an API to access the controller
status.  That API uses HTTP.

Siemens: is an organisation that probably provides hardware for
traffic lights controllers to be used in America (USA).

Architectures: sketches drawing controller, tri-light bulbs, Internet,
802.11-OCB, car, API, SPAT.

Acknowledgements: Daniele Brevi, Bart Netten, Stephane Goeuriot, Sri
Gundavelli, Bruno Cabon, Paul Thorpe.