Reading review problem. Consider the following summary of a risk analysis conducted from M...

Reading review problem. Consider the following summary of a risk analysis conducted from May to July 2003 (den Braber et al., 2005):

NetCom is one of the main mobile phone network providers in Norway. Their “MinSide” application of ers their customers access to their personal account information via the Internet, enabling them to view and change the properties of their mobile phone subscription. “MinSide” deals with a lot of sensitive customer information that needs to be secure, while at the same time being easily available to the customer in order for the service to remain usable and competitive. The goal of the analysis was to identify risks in relation to the use of the “MinSide” application and, where possible, suggest treatments for these risks. This was achieved through two model-driven brainstorming sessions based on system documentation [including] data flow diagrams.

You can find NetCom’s Web page (written in Norwegian) at http://www.netcom.no. Source: F. den Braber, A. Mildal, J. Nes, K. Stolen, and F. Vraaslsen, “Experiences from Using the CORAS Methodology to Analyze a Web Application,” Journal of Cases on Information Technology (July–September 2005), pp. 110–30.

a. Data flow diagrams incorporate four symbols. Identify those symbols and suggest how each might be applied in the NetCom case.

---

b. NetCom would need to maintain a database of customer records; that database would likely include (at a minimum) a customer table and a subscription table. Create specifications (field names) for both tables, indicating primary keys by underlining and foreign keys with brackets.