After publishing the article on “How to send WAP Push data through SMPP”, there is a lot of requests on how to formulate the GSM SMS User Data.

Basically, the following is an example in java with remark in the code to explain how this is done:

  public String toSmsBinary() {
    /**
     GSM SMS User Data
     06: UDH Length which is 6
     05: 16 bit address
     04: Length(4)
     0B84: Destination Port(2948)
     23F0: Source Port(9200)

     Wireless Session Protocol
     90: Transaction ID
     06: PDU Type(Push)
     01: Headers Length is 1
     AE: Content-Type is application/vnd.wap.sic

     */
    StringBuilder ud = new StringBuilder().append("0605040b8423f0900601ae");
    ud.append(toWBXML());
    return ud.toString();

  }

The above function creates the GSM SMS User Data and Wireless Session Protocol (WSP) header. Read the rest of this entry »

Here we would like to show you how to send a WAP Push message through SMPP using Java. This short tutorial will use the library and example source code from OpenSMPP. You can download the file from SourceForge.

The downloadable zipped file include source code and jar file libraries, and this article will modify this file SMPPTest.java to demonstrate how to do that.

Modify SMPPTest.java and include the following 2 functions:

    private static final String HEXINDEX = "0123456789abcdef          ABCDEF";

    public static byte[] hexToByte(String s) {
        int l = s.length() / 2;
        byte data[] = new byte[l];
        int j = 0;

        for (int i = 0; i < l; i++) {
            char c = s.charAt(j++);
            int n, b;

            n = HEXINDEX.indexOf(c);
            b = (n & 0xf) << 4;
            c = s.charAt(j++);
            n = HEXINDEX.indexOf(c);
            b += (n & 0xf);
            data[i] = (byte) b;
        }
        return data;
    }

The above function is used to convert Hexadecimal to binary data.
Read the rest of this entry »