Introduction

Using the SMPP protocol, an SMS application system called the �External Short Message Entity� (ESME) may initiate an application layer connection with an SMSC over a TCP/IP network connection and may then send short messages and receive short messages to and from the SMSC respectively. The ESME may also query, cancel or replace short messages using SMPP. SMPP supports a full featured set of two-way messaging functions such as:

• Transmit messages from an ESME to single or multiple destinations via the SMSC
• An ESME may receive messages via the SMSC from other SME�s (e.g. mobile stations).
• Query the status of a short message stored on the SMSC
• Cancel or replace a short message stored on the SMSC
• Send a registered short message (for which a �delivery receipt� will be returned by the SMSC to the message originator)
• Schedule the message delivery date and time
• Select the message mode, i.e. datagram or store and forward
• Set the delivery priority of the short message
• Define the data coding type of the short message
• Set the short message validity period
• Associate a service type with each message e.g. voice mail notification

SMPP Resource Adaptor

The SMPP Resource adaptor adopts SMSC to the requirements of the SLEE and built on top of the implementation of the SMPP. The source code for the core SMPP stack implementation can be found at http://smppapi.sourceforge.net. The source code of the RA implementation located https://mobicents.dev.java.net/source/browse/mobicents/ra/smppra/. The SMPP RA defines the follwing resource adaptor concepts.

SMPP Resource Adaptor Type

Resource adaptor type identifier

Activity objects

Events

Event types

Event classes

• net.java.slee.resource.smpp.RequestEvent
• net.java.slee.resource.smpp.ResponseEvent

Activity Context Interface Factory Interface

import javax.slee.ActivityContextInterface;
import javax.slee.FactoryException;
import javax.slee.UnrecognizedActivityException;

public interface RadiusActivityContextInterfaceFactory {
    public ActivityContextInterface getActivityContextInterface(ClientTransaction tx)
        throws NullPointerException, UnrecognizedActivityException, FactoryException;
    
    public ActivityContextInterface getActivityContextInterface(ServerTransaction tx)
        throws NullPointerException, UnrecognizedActivityException, FactoryException;

    public ActivityContextInterface getActivityContextInterface(Dialog dialog)
        throws NullPointerException, UnrecognizedActivityException, FactoryException;

}

Resource adaptor object

Configuration

• host: The name of the host (or IP-address string) of the SMPP server. Used to establish connection with SMSC in TCP/IP network. Default: localhost
• port: The port number used by SMPP server to establish connection. Default: 2775
• systemId: Used as login name to authenticate connection with SMPP server. Default: 1
• systemType: Identifies the type of system. Default:ESME.
• password: Used as password to authenticate connection with SMPP server. Default:1
• addressTon: The default type of number (TON) that should be on received messages.Default:1
• addressNpi: The default number plan indicator (NPI) that should be on received messages.Default:0
• addressRange: For receivers this specifies the range of numbers for which messages are to be received. This is usually a regular expression but may be server implementation dependent. Default:0020.
• enquireLinkTimeout: SMPP link timeout in seconds, used to reconnect. Default: 30

The SLEE administartor can override default settings of the resource adaptor entity at the deployment time. The one way is consisted in specifying the URL pointed to properties file as an argument to the CLI's method createResourceAdaptorEntity().

Example

We will work in a "client" mode. It is not a matter for this example application but it just means that GoogleTalk^? users will see mobile domain as virtual user, and this user should be registered in the contact list. Same is for the mobile subscriber, there is a predefined mobile number (short or full) wich will serves as gateway to the GoogleTalk^? domain. And in both cases, the additional, native for other side, address should be specified in the message body to allow recognize the recipient of the message. So the follwing message format may be adopted for the gateway:

addressString Message_text

where addressString is native for the domain user address: The mobile number in E164 format for messages addressed to mobile user and gmail address for messages addressed to GoogleTalk^? user.

Source code

Accesing resource adaptor from Sbb

public void setSbbContext(SbbContext sbbContext) {
        this.sbbContext = sbbContext;
        try {
            logger.info("Called setSbbContext PtinAudioConf!!!");
            Context myEnv = (Context) new InitialContext().lookup("java:comp/env");
            xmppProvider = (XmppResourceAdaptorSbbInterface) 
                    myEnv.lookup("slee/resources/xmpp/2.0/xmppinterface");
            smppProvider = (SmppProvider) 
                    myEnv.lookup("slee/resources/smpp/3.4/smppinterface");            
            smppAcif = (ActivityContextInterfaceFactory) 
                    myEnv.lookup("slee/resources/smpp/3.4/factoryprovider");
        } catch (NamingException ne) {
            logger.warn("Could not set SBB context:" + ne.getMessage());
        }
}

Handling server transactions

    public void onSmsMessage(RequestEvent event, ActivityContextInterface aci) {
            logger.info("Sending message to " + address);
            ....
            event.getTransaction().respond(Transaction.OK);
    }

Handling client transactions

    public void onGoogleMessage(Message message, ActivityContextInterface aci) {
        Dialog dialog = smppProvider.getDialog(address, "0020");
        
        ShortMessage sms = dialog.createMessage();
        sms.setText(txt);
        
        ClientTransaction tx = dialog.createSubmitSmTransaction();
        ActivityContextInterface ac = smppAcif.getActivityContextInterface(tx);
        ac.attach(sbbContext.getSbbLocalObject());
        tx.send(sms);
}

Howto install, setup and run

• Get updated version of mobicents and mobicents-examples from CVS.
• Create 2 accounts on gmail .
• Login in Google Talk through one account .
• Use other account to set the username and password in Google Talk Bot Sbb.java
• For example if the gmail account is mgsgateway@gmail.com , then in Google Talk Bot Sbb.java it will look like this : private final String username = "msggateway" Similarliy set your password .
• Add the above account as your buddy in the Google Talk .
• Run mobicents .
• Run SMPPSim
• Deploy the XMPP RA .
• Deploy the SMPP RA.
• Deploy the message gateway example.

Now use the "Mobile landscape" thml page, shipped with SMPPSim, to send a message (like from mobile device). Put 0020 to the destination_address field and type your message in the short_message field. The message format specified above should be used. For example: some_user@gmail.com hi. The message "hi" will be delivered, you can then answer typing in the GoogleTalk^? the mobile address of the recipient and message body.

Related resources

• [[http://www.seleniumsoftware.com/downloads.html[SMPP Simulator]]

Waht's next.

-- Main.ivelin - 06 Jul 2006