OpenWebNet

<h2 id="openwebnet-protocol">OpenWebNet Protocol</h2>
<p>The protocol is thought to be independent from the used technology. For example, it is possible to use a supervisor software connected via <a href="/facts/Ethernet/nMfhU8tU">Ethernet</a>, via serial <a href="/facts/RS-232/NCpvGuyq">RS-232</a> or via <a href="/facts/USB/XcIKWLyg">USB</a> to a gateway that is directly connected to a domotic system. One can require protocol message extension. It is enough to propose their own <a href="/facts/Request_for_Comments/esftTvE7">RFC</a>. It will be examined and disclosed if it respects  <i>OpenWebNet</i> syntax.
</p>
<h3>Syntax</h3>
<p>An <i>OpenWebNet</i> message is structured with variable length fields separated by the special character '*' and closed by '##'.
</p><p>The characters admitted in the fields are numbers and the character “#”.
</p><p>The structure of a message is therefore:
</p>
<ul><li>field1*field2*… *fieldN##</li></ul>
<p>The following fields are admitted:
WHO
WHAT
WHERE
DIMENSION
VALUE
</p><p>WHO
</p><p>It characterizes the domotic system function to which the OpenWebNet message is referred.
</p><p>For example: WHO = 1, characterizes the messages for lighting system management.
</p><p>WHAT
</p><p>It characterizes an action to do or a status to read. For every WHO (and therefore for every function) there is a specific WHAT table.
</p><p>The field WHAT can also contain optional parameters: WHAT#PAR1#PAR2… #PARn.
</p><p>Example of actions: switch ON light, dimmer to 75%, switch DOWN shutter, radio ON, etc. 
Example of status: light ON, active alarm, battery unload, etc.
</p><p>WHERE
</p><p>It characterizes the set of objects to which the OpenWebNet message is referred. It can be a single object, a group of objects, a specific environment, the entire system, etc.
</p><p>For every WHO (and therefore for every function) there is a specified WHERE table.
</p><p>The tag WHERE can also contain optional parameters: WHERE#PAR1#PAR2… #PARn.
</p><p>Example of where: all the lights of group 1, sensor 2 of zone 1 of alarm system, etc.
</p><p>DIMENSION
</p><p>Is a range of value that characterizes the dimension of the object to which the message is referred. For every WHO (and therefore for every function) there is a specific DIMENSION table.
</p><p>It’s possible to require/to read/to write the value of one dimension.
Every dimension has a prefixed number of values, described in VALUE field.
</p><p>Example of dimension: sensor temperature, loudspeaker volume, firmware version of a device, etc.
</p><p>VALUE
</p><p>It characterizes the read/written value of a written/required/read dimension.
</p>
<h3>Message</h3>
<p>There are 4 types of OpenWebNet Message:
</p>
<ul><li>Command / Status Message</li>
<li>Status Request Message</li>
<li>Request/Read/Write Dimension Message</li>
<li>Acknowledge Message</li></ul>
<p><i>Command / Status Message</i>
</p>
*WHO*WHAT*WHERE##

<p><i>Status Request Message</i>
</p>
*#WHO*WHERE##

<p><i>Request/Read/Write Dimension Message</i>
Request:
</p>
*#WHO*WHERE*DIMENSION##

<p>Read:
</p>
*#WHO*WHERE*DIMENSION*VALUE1*...*VALUEn##

<p>Write:
</p>
*#WHO*WHERE*#DIMENSION*VALUE1*...*VALUEn##

<p><i>Acknowledge Message</i>
ACK:
</p>
*#*1##

<p>NACK:
</p>
*#*0##

<h2 id="gateway-openwebnet">Gateway OpenWebNet</h2>
<p>It is possible to interact with the SCS <a href="/facts/Home_automation/kfz6C07m">home automation</a> <a href="/facts/Bus_(computing)/R45TKwS7">bus</a> by using a specific <a href="/facts/Gateway_(telecommunications)/YTYSqhqN">gateway</a>.
</p><p>There are two typologies of gateways that allow a connection to the field bus by using different <a href="/facts/Technical_standard/P4orT1SM">standard</a> <a href="/facts/Communications_protocol/5uady7cB">protocols</a>:
</p>
<ul><li>Gateway <a href="/facts/Ethernet/nMfhU8tU">Ethernet</a> (<a href="/facts/Linux/9FvCKSTq">Linux</a>-based)</li>
<li>Gateway <a href="/facts/USB/XcIKWLyg">USB</a> or <a href="/facts/RS-232/NCpvGuyq">RS-232</a></li></ul>
<h3>Gateway Ethernet</h3>
<p>The current implementation by BTicino is also an <a href="/facts/Embedded_system/a4muX1wU">embedded</a> <a href="/facts/Web_server/A4GS6thA">web server</a>. It works as a translator between OpenWebNet messages via TCP/IP and the SCS messages transmitted on the SCS bus.
</p><p>It is possible to control three different kinds of buses:
</p>
<ul><li>BUS SCS</li>
<li><a href="/facts/KNX_(standard)/ftmDyKRw">KNX</a></li>
<li><a href="/facts/Digital_MultipleX/B9WSCzpW">DMX</a></li></ul>
<p>The Ethernet gateway offers two modes of authentication:
</p>
<ul><li>via a list of whitelisted IPAs</li>
<li>using a nonce-type password exchange (see in the external links for code) (used on older devices)</li>
<li>using a hmac based authentication algorithm (can be found in the documentation, external links) (used on newer devices)</li></ul>
<p>Usually, the default port for the Ethernet gateway is 20000 even if the registered port for the protocol is 20005.
</p>
<h3>Gateway USB or RS-232</h3>
<p>The gateway is an interface that works as a translator between the OpenWebNet messages transmitted on USB or serial and the SCS messages transmitted on the SCS bus.
</p>
<h2 id="functions">Functions</h2>
<table><tbody><tr><th>WHO value</th><th>Function</th></tr><tr><th>0</th><td>Scenario</td></tr><tr><th>1</th><td>Lighting</td></tr><tr><th>2</th><td>Automation</td></tr><tr><th>3</th><td>Load control</td></tr><tr><th>4</th><td>Temperature Control/Heating</td></tr><tr><th>5</th><td>Burglar Alarm/Intrusion</td></tr><tr><th>6</th><td>Door Entry System</td></tr><tr><th>7</th><td>Video Door Entry System/multimedia</td></tr><tr><th>9</th><td>Auxiliary</td></tr><tr><th>13</th><td>Gateway/interfaces management</td></tr><tr><th>14</th><td>Light+shutters actuators lock</td></tr><tr><th>15</th><td>CEN/Scenario Scheduler, switch</td></tr><tr><th>16</th><td>Sound System/Audio</td></tr><tr><th>17</th><td>Scenario programming</td></tr><tr><th>18</th><td>Energy Management</td></tr><tr><th>24</th><td>Lighting Management</td></tr><tr><th>25</th><td>CEN/Scenario Scheduler, buttons</td></tr><tr><th>1000</th><td>Diagnostic</td></tr><tr><th>1001</th><td>Automation diagnostic</td></tr><tr><th>1004</th><td>Thermoregulation diagnostic failures</td></tr><tr><th>1013</th><td>Device diagnostic</td></tr></tbody></table>
<table><tbody><tr><th>WHERE value</th><th>Lighting Function</th></tr><tr><th>0</th><td>General</td></tr><tr><th>1÷9</th><td>Room 1÷9</td></tr><tr><th>11÷99</th><td>Light point 11÷99</td></tr><tr><th>#1÷#9</th><td>Group 1÷9</td></tr></tbody></table>
<h2 id="example">Example</h2>
<p>OpenWebNet message examples
</p><p>Command Message
</p><p>Switch Off of light 77
</p>
*1*0*77##

<p>WHO = 1
WHAT = 0
WHERE = 77
</p><p>Status Message
</p><p>Scenario 1 of scenario unit 23 activated.
</p>
*0*1*23##

<p>WHO = 0
WHAT = 1
WHERE = 23
</p><p>Request status message
</p><p>Status request of probe 1
</p>
*#4*1##

<p>WHO = 4
WHERE = 1
</p><p>Request Dimension Message
</p><p>Request of Temperature Measured, probe 44
</p>
*#4*44*0##

<p>WHO = 4
WHERE = 44
DIMENSION = 0
</p><p>Read Dimension Message
</p><p>Temperature Measured, probe 44
</p>
*#4*44*0*0251*2##

<p>WHO = 4
WHERE = 44
DIMENSION = 0
VALUE1 = 0251 (T=+25,1 °C)
VALUE2 = 2 (System in "cooling mode")
</p><p>Write Dimension Message
</p><p>Volume set at 50%, environment 2
</p>
*#16*#2*#1*16*##

<p>WHO = #16
WHAT = #2
WHERE = #1
DIMENSION = 1
VALUE1 = 16
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Home_automation/kfz6C07m">Home automation</a></li>
<li><a href="/facts/KNX_(standard)/ftmDyKRw">KNX</a></li>
<li><a href="/facts/Digital_MultipleX/B9WSCzpW">DMX</a></li></ul>

<ul><li>Moneta, D. Mauri, G. Bettoni, C. Meda, R. - Cesi ricerca (Italy) <i><a href="https://web.archive.org/web/20110706133239/http://www.cired.be/CIRED07/pdfs/CIRED2007_0522_paper.pdf">https://web.archive.org/web/20110706133239/http://www.cired.be/CIRED07/pdfs/CIRED2007_0522_paper.pdf</a> Test Facility for the assessment of local energy management systems</i>; 19th Conference on Electricity Distribution, Vienna (21–24 May 2007).</li>
<li>Moneta, D. Bisone, L. Mauri, G. Meda, R. - Cesi ricerca (Italy) <i><a href="https://ieeexplore.ieee.org/document/4209527/;jsessionid=961A3F8772A9F5137915F077D02C56FB?tp=&arnumber=4209527&isnumber=4209049">https://ieeexplore.ieee.org/document/4209527/;jsessionid=961A3F8772A9F5137915F077D02C56FB?tp=&arnumber=4209527&isnumber=4209049</a> New interactions between LV customers and the network: further possibilities for home automation functions  </i>; IEEE International Conference on Robotics and Automation, Rome (10–14 April 2007).</li>
<li>Bonino, D. Castellina, E. Corno, F. - Politecnico di Torino (Italy) <i><a href="http://www.cad.polito.it/pap/db/ictai08.pdf">http://www.cad.polito.it/pap/db/ictai08.pdf</a>[<i>permanent dead link</i>‍] DOG: an Ontology-Powered OSGi Domotic Gateway</i>; Torino (September 2008).</li></ul>
<h2 id="external-links">External links</h2>
<ul><li><a href="http://www.myopen-bticino.it">MyOpen Bticino</a></li>
<li><a href="https://www.iana.org/assignments/port-numbers">IANA, TCP ports assignment.</a> OpenWebNet is associated to port 20005, but uses by default the port 20000</li>
<li><a href="https://developer.legrand.com/Documentation/">Documentation</a></li>
<li><a href="https://rosettacode.org/wiki/OpenWebNet_password">Password exchange code</a></li></ul>

OpenWebNet open-in-new

OpenWebNet