Async MQTT-SN over UDP and XBee

• Async MQTT-SN Gateway running on linux
• Async MQTT-SN Client running on linux and Arduino Uno, Arduino Ethernet.
• Design concept of Async client is defferent from Sync one. No more MQTT-SN Message classes.
• Program size of Async client over UDP for Arduino is 21KB. over XBee is 16KB.
• Gateway is changed to support Async PUBACK and SUBACK, DISCONNECT　responce.

For details, see Wiki

Supported functions

• QoS Level 0, 1, 2
• SEARCHGW, GWINFO
• CONNECT, WILLTOPICREQ, WILLTOPIC, WILLMSGREQ, WILLMSG
• PINGREQ, PINGRESP
• CONNACK, REGISTER, REGACK, SUBACK, PUBACK, UNSUBACK
• SUBSCRIBE, PUBLISH, UNSUBSCRIBE, DISCONNECT

Implemented control flows:
Application program executes PUBLISH() function,
Protocol flow as berrow is conducted automaticaly.

             Client              Gateway               Broker
  user coding   |                   |                    |      
                |                   |                    |    
   PUBLISH() -->| --- SERCHGW ----> |                    |  
                | <-- GWINFO  ----- |                    |  
                | --- CONNECT ----> |                    |  
                | <--WILLTOPICREQ-- |                    |  
                | --- WILLTOPIC --> |                    |  
                | <-- WILLMSGREQ -- |                    |  
                | --- WILLMSG ----> | ---- CONNECT ----> |(accepted)     
                | <-- CONNACK ----- | <--- CONNACK ----- |  
                | --- SUBSCRIBE --> | ---- SUBSCRIBE --> |     
 [set Callback] | <-- SUBACK ------ | <--- SUBACK ------ |   
                | --- REGISTER----> |                    |  
                | <-- REGACK  ----- |                    |  
                | --- PUBLISH ----> | ---- PUBLISH ----> |      
                | <-- PUBREC  ----- | <---- PUBREC ----- |    
                | --- PUBREL  ----> | ----- PUBREL ----> |    
                | <-- PUBCOMP ----- | <---- PUBCOMP----- |        
                |                   |                    |        
                //                  //                   //      
                | --- PINGREQ ----> | --- PINGREQ ---->  |         
                | <-- PINGRESP----- | <-- PINGRESP-----  |                    
                //                  //                   //    
                |                   |                    |    
                | <-- REGISTER ---- | <--- PUBLISH ----- |<-- PUBLISH  
                | --- REGACK  ----> |                    |  
[exec Callback] | <-- PUBLISH  ---- |                    |  
                | --- PUBACK   ---> | ---- PUBACK  ----> |--> PUBACK  
                |                   |                    |  
                //                  //                   //       
                |                   |                    |    
DISCONNECT() -->| ---DISCONNECT---> |                    |  
                | <--DISCONNECT---- |                    |           

License

This source code is available under the MIT license