diff --git a/README.md b/README.md
index f61c71b..8093f01 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Receive SMS on his desk in order to use the content.
     - The messages are received on an MQTT client installed on the laptop (1 or more).
     - The messages are then sent to the recipients.
 
-####SMS reception
+#### SMS reception
 
 - The SMS are received on the mobile and published to the MQTT server
 - The messages are received on an MQTT client installed on the subscribed machine (1 or more)
@@ -31,3 +31,145 @@ Receive SMS on his desk in order to use the content.
 - Email message usage
 - Receive and process alert messages (IOT or other)
 - etc ...
+
+#### Conditions for receiving or sending
+- Take a public or private MQTT server to relay messages
+- Subscribe MQTT customers to the same topics
+
+> You can install your own mosquitto server
+>> https://mosquitto.org/download/
+>
+> More information on MQTT: https://fr.wikipedia.org/wiki/MQTT
+
+- Security of data transmitted
+> We may need to encrypt the content for security reasons.
+>> Use encryption with public key / private key on clients
+
+#### Non-exhaustive use
+- Complement of the email message
+- Receive and process alert messages (IOT or other)
+- etc ...
+
+### Installation
+
+https://github.com/termux/termux-app
+
+#### Installation of termux
+- Termux application obtained by F-Droid:
+    - https://www.f-droid.org/fr/
+
+- Or by google store:
+    - https://play.google.com/
+
+> IMPORTANT: We will choose either one or the other.
+
+- Install
+    - Termux
+    - Termux: API
+    - Termux: Widget
+
+#### Installing the mqtt client:
+
+The following python packages will be installed:
+
+- termux-sms-gateway
+- paho-mqtt
+- rsa >> https://stuvel.eu/python-rsa-doc/
+
+### Installation procedure
+
+After installing termux on the laptop, launch Termux
+
+- Copy and paste the following command in the terminal
+
+        export PACKAGE="TermuxSmsGateway"&&export VERSION="1.0"&&mkdir -p $HOME/.termux/tasks&&
+        apt install termux-api git -y&&rm -rf termux-sms-gateway&&
+        git clone &&
+        cp -f $PACKAGE/smsquitto-st* $HOME/.termux/tasks/&&cp -f $PACKAGE/smsquitto/smsquitto-conf.yaml $HOME/.termux/&&
+        pip install $PACKAGE/dist/smsquitto-$VERSION.tar.gz
+
+- Enter to start the installation
+
+### Installation parameters
+
+- The installation parameters are in ~ / .termux / smsquitto-conf.yaml
+    - host: ip or domain of the MQTT server
+    - port: 1883 or 8883
+    - keepalive: 60
+    - username: login
+    - password: password
+    - useSSL: False or True
+    - ca_cert: path/of/file/ca.cert
+    - apikey: *string*
+
+        - ** IMPORTANT **: This key is used to synchronize the topics with the subscriptions
+            - ex: SQTT010203040506079
+
+- Copy and paste the following command in the terminal
+
+        nano $HOME/.termux/smsquitto-conf.yaml
+
+- Install the service
+
+     - Install the Tremux widget:Widget on the phone's desktop by keeping your finger on the screen
+     - Choose shortcut
+     - Change the icon and the name if you want
+     - Start the service by clicking the icon
+
+### Uses
+
+- An MQTT client is required to operate the phone.
+    - The smsquittod.py module gives an example of a client written in python.
+        - The library used is that of the Eclipse foundation: pahon-mqtt
+        - It will suffice to implement the ClientMQTTBase class
+
+    - The sms-client-test.html file is another example but in websocket mode.
+        - It will suffice to directly modify the html file
+        - we launch it directly in a browser
+            - by drag and drop
+            - by an address of this type
+                - file: ///path/du/fichier/sms-client.html
+
+- demonstration
+
+     - sms-client-test.html is fully functional
+     - You just have to update the apikey in this file and in the configuration file on the mobile phone
+     - And set up some mobile numbers to do the tests
+
+### Domotiz
+
+- https://www.domoticz.com/wiki/Getting_started
+
+- Send notification from custom HTTP/Action
+
+    - Notification
+        - script://notify.sh #FIELD1 #FIELD2 #FIELD3 #FIELD4 #TO #MESSAGE --tls or nothing
+            - /usr/bin/python3 /home/pi/domoticz/scripts/notify.py --method=notify --host=$1 --port=$2 --user=$3 --password=$4 --apikey=$5 --text="$6" $7
+
+    - SMS
+        - script://notify.sh #FIELD1 #FIELD2 #FIELD3 #FIELD4 #TO #MESSAGE "00330645953706,0033791246318" --tls or nothing
+            - /usr/bin/python3 /home/pi/domoticz/scripts/notify.py --method=sms --host=$1 --port=$2 --user=$3 --password=$4 --apikey=$5 --text="$6" --phone="$7" $8
+
+    - SSL certification
+        - argument --tls, in $7 or $8.
+        - the certification key is in domoticz/scripts/notify.py. Thinking of modifying it.
+
+    - You must install python3 paho-mqtt library: pip3 install paho-mqtt
+
+### Orders
+
+Messages sent and received on the phone are in this form
+
+- (topic, payload)
+    - topic: is a character string that starts with apikey see above
+        - apikey/pub/sms
+        - apikey/emit/inbox
+    - payload: is a Json string
+        - {mobile: [mobile1, mobile2, etc ...], subject: "the subject", msg: "the message"}
+        - {time: time, payload: payload}
+- orders
+    - apikey/pub/sms send an sms
+    - apikey/pub/notify send notification to phone
+    - apikey/pub/location request for Geographic positioning
+    - apikey/pub/inbox or all or sent or draft or outbox Read SMS
+    - apikey/pub/kill-service stop the service on the phone