Activating Services By Textual Requests

SGA-USSD is a modular system for supporting enquiry, activation, deactivation or modification of service statuses from the user’s mobile terminal. The usage of such USSD-based applications are as simple as dialing *123*key# - this example would send “key” to service number 123, where the appropriate server would answer the request.
AITIA provides a complete, modular, and scalable solution for such services by offering its own implementation of the USSD Gateway as well as several standalone services and multipurpose database interfaces.

USSD-Based Solutions

AITIA has lots of experience in creating and maintaining complete USSD-based solutions as well as USSD-based service-logic elements. Such services include:

• account balance enquiry
• account recharge using a voucher number
• roaming services activation/deactivation
• info-SMS request (e.g., on roaming charges)
• call-back applications
…and many more.

USSD Solutions From AITIA

SGA-USSD provides full USSD Gateway functionality with various applications from roaming activation through balance enquiry to micropayment interfaces. The SGA-USSD platform consists of two main functional parts: the gateway (SGA-USSD-GW system), and the service logics.

Modularity

There are multiple reasons for proposing the USSD-platform in such a modular manner:

• it is more scalable
• it is easier to maintain; it requires only a module addition when introducing a new USSD service
• the USSD-GW remains untouched.

Moreover, the USSD-Gateway can reside in the same machine together with some service logic programs; other services can be homed in separate machines.

Core Gateway Functionality

The SGA-USSD-GW module serves the USSD-based requests arriving on SS7/MAP protocol by identifying the service code in the request and forwards the contents to the appropriate service logic module via TCP/IP. During the first handshake (after startup) between the USSD-GW and the given Service Logic Module (SLM) they clarify which USSD code(s) belong(s) to the SLM. Once this has been dealt with, the gateway forwards the USSD request contents to the SLM. The SLM’s answer (received on the TCP/IP connection) is converted back to a standard MAP USSD answer and gets forwarded by the gateway (over the SS7 connection). The module also takes care of multiple requests, and (in Detailed or Debug log level) logging of requests and responses.

Capacity Considerations

One of our current USSD-platforms handles over 150.000 (one hundred and fifty thousand) requests per a normal hour, and twice this much in a busy hour. This limit is only due to the link capacity, the platform (processor, memory, software, etc.) consumes very little of the resources.

Hardware and Software Configuration

The duplicated system includes 1+1 USSD server machine of industrial grade PCs and SGA-47 interface cards for SS7 connections. A fully duplicated system requires two 19” industrial grade PCs, containing:

• redundant HDD (e.g., 160 GB SATA)
• redundant power supply
• passive motherboard with slots to fit several SGA-47 cards
• active processor board
• processor: Intel Core2 Duo – or similar
• memory: 4 GB

For SS7 connections SGA-47 interface cards are required; SIGTRAN connections can be handled by any industrial grade Ethernet cards.