paho.mqtt-sn.embedded-c/MQTTSNGateway

MQTT-SN requires a MQTT-SN Gateway which acts as a protocol converter to convert MQTT-SN messages to MQTT messages. MQTT-SN client (UDP) can not communicate directly with MQTT broker(TCP/IP).

step1. Build the gateway

$ git clone -b gateway https://github.com/eclipse/paho.mqtt-sn.embedded-c 
$ cd paho.mqtt-sn.embedded-c       
$ make   
$ make install   
$ make clean
```       
MQTT-SNGateway, MQTT-SNLogmonitor and param.conf are copied into ../ directory.

    
### **step2. Execute the Gateway.**     

$ cd ../
$ ./MQTT-SNGateway

        
MQTT-SN clients should run in differnt from a host of the gateway. Other wise the gateway can't receive multicast packets form clients.    

### **How to Change the configuration of the gateway**    
**../param.conf**   Contents are follows: 
   

config file of MQTT-SN Gateway

BrokerName=test.mosquitto.org
BrokerPortNo=1883
SecureConnection=NO
#BrokerPortNo=8883
#SecureConnection=YES
ClientAuthorization=NO
GatewayID=1
GatewayName=PahoGateway-01
KeepAlive=900
#LoginID=
#Password=

UDP

GatewayPortNo=2000
MulticastIP=225.1.1.1
MulticastPortNo=1883

XBee

Baudrate=38400
SerialDevice=/dev/ttyUSB0

**BrokerName** to specify a domain name of the Broker, and **BrokerPortNo** is a port No of the Broker. If the Broker have to connected via TLS, set BrokerPortNo=8883 and **SecureConnection=YES**.     
**MulticastIP** and **MulticastPortNo** is a multicast address for ADVERTISE, GWSEARCH and GWINFO messages. Gateway is waiting GWSEARCH multicast message and when receiving it send GWINFO message via Broadcast address. Clients can get the gateway address (Gateway IP address and **GatewayPortNo**) from GWINFO message by means of std::recvfrom(),
Client should know the BroadcastIP and PortNo to send a SEARCHGW message.    
**GatewayId** is defined by GWSEARCH message.    
**KeepAlive** is a duration of ADVERTISE message in seconds.    
when **ClientAuthorization** is YES, see MQTTSNGWClient.cpp line53, /usr/local/etc/mqttsnGateway/config/clientList.conf file is required. this file defines connect able clients by IPaddress and PortNo.    


### ** How to change the config files directory. **
    
The directory is defined in MQTTSNGWProcess.h line33.    
change this value to new directory you want to use.
       
`#define MQTTSNGW_CONFIG_DIRECTORY "./"`

### ** How to monitor the gateway from remote. **

Uncomment line32 in MQTTSNGWDefined.h.

`//#define RINGBUFFER     // print out Packets log into shared memory./"`    

$ make
$ make install $ make clean

restart the gateway.    
open ssh terminal and execute LogMonitor.

`$ ./MQTT-SNLogmonitor`    

Now you can get the Log on your terminal.