SMS messages using USB Modem

This guide uses gnokii-sms to send and receive SMS messages using Linux PC. The project I was working on did not require industrial grade throughput. That is the reason I cannot justify the cost of WaveComm iTegra type equipment. The SMS project was ran on a Debian Linux. If you are using a different distro, use the packaging mechanism of your distro.

There were a couple of other solution approaches but I went for gnokii-sms. I didn’t have a lot of time, which ruled out whipping serial I/O codes and concocting SMS messages using Hayes AT command set.

I could have used Kannel but it was so big. I only needed a simple mechanism to receve and send SMS message. I did not need a full gateway with all the bells and whistles.

GNOKii-SMS and Gammu were mature solutions. I went eventually with gnokii-sms but Gammu would have been a fit as well.

Hence, this mashup uses gnokii-sms. It is a stand-alone application with a daemon and it uses MySQL database as a datastore. I don’t need to learn any API in order to integrate it with my application. All I need to do is to write an application that will query the gnokii-sms backend. I won’t even alter the structure of the gnokii-sms database. My application will simply use gnokii for the SMS facility. No application logic will be added to gnokii-sms

This little project requires the following

  1. A Linux PC. Debian was used but I got to test it on Crunchbang as well, worked out fine. It should work fairly well on the Debian derivatives e.g. Ubuntu, Xubuntu, Mint etc
  2. A USB modem. A post paid plan was used for the project, but a USB stick on pre-paid should work just as well

Installation

sudo apt-get update
sudo apt-get install mysql-server
sudo apt-get install gnokii-smsd-mysql

Config

Connect the USB modem to PC and find out which port it is using

sudo lsusb

Another command to use could be

sudo dmesg | grep USB

What you are looking for is the device name for the modem. Usually, the modem is at /dev/tty0, but just to be sure, run either lsusb or the dmesg command as stated above. Remember the device name because you will need it when you edit ~/.config/gnokii/config — that is the configuration file for gnokii.

On some Debian derivatives like Crunchbang, the gnokii config file was not created during the installation . If that is the case, just create the config file manually.

sudo mkdir -p ~/.config/gnokii
sudo touch ~/.config/gnokii/config

Edit the config file. Set the port number and model to their appropriate values

port=/dev/tty0
model=AT

There might a default value for the model property, it could be 6510. That value corresponds to a Nokia phone. But we are not using a Nokia phone, we are using a USB modem, so set the model value to AT.

Once done with the configuration, just do a quick test so that we know things are working out fine. Gnokii has a command that can quickly tell us if we are doing things correctly.

sudo gnokii --identify

It should give us some diagnostics and a quick peek if we did something wrong on the configuration file.

Database backend

The gnokii-smsd-msyql package contains the SQL scripts necessary to create the table structure, but the database itself still needs to be manually prepared.

mysql -u root -p
mysql> create database smsgw;
mysql> use smsgw;
mysql> \. /usr/share/doc/gnokii-smsd-mysql/sms.tables.mysql.sql;

Sending and Receiving SMS

First, the daemon smsgw daemon process needs to run. Get another terminal window and run the daemon process from there

sudo smsd -u root -p smsgw -c localhost -m mysql

To send an SMS message, the command is

echo "Test message | gnokii --sendsmsd +MobileNumber

+MobileNumber is structured as (country code) phone number

If you send an SMS message to the number of the USB modem, all incoming messages are stored in the inbox table of the database

mysql -u root -p
mysql> use smsgw;
mysql> select * from inbox;

Footnotes:

1 There was a gnokii config file though at `/etc/xdg/gnokii/config`, this was probably meant to be copied over to `~/.config/gnokii/config`