Graphic depicts a big box representing Service Broker. Inside the Service Broker box from top to bottom are Balance Manager Service and Balance Manager Web Service connected by two-way arrows. The Balance Manager Web Service is connected by two-way arrows labeled "WS Requests" to SMS, IVR and WEB boxes outside the Service Broker box; these represent the external interfaces.
The Balance Manager Service is connected by two-way arrows outside the Service Broker box to an oval representing BRM, which itself is connected to two databases: Subscriber DB and Voucher DB.