Telecommunication Case Study

Description

The case study described below is about mobile phone services portability. Voice and data services are provided by a set of mobile telecommunication companies around Europe. There companies are usually called Cell Phone Operators (CPOs). Some of these CPOs operate in a single country, whereas some others are big CPOs that have branches in several countries. Inhouse services are offered by the CPO to manage all the customers and the stipulated contracts. Moreover the customers can view personal information about their contracts accessing to a suitable services made available by the telephone operator, or some user could query all the services offered by the CPO accessing its public services. Not all the CPOs have their own telecom infrastructures; some of them rent the network services from big telecom companies and provide a service to the users. Such operator are called Virtual Operators (VOs). The case study presented in this chapter is about the additional services that a company support to allow the portability of the phone number and the portability of services. The possibility to change a mobile phone operator without changing the mobile phone number is one of the mandatory services that a mobile phone operator must provide. National and European laws regulate this procedure with the aim of allowing the customers to freely select the best company according to their requirements to be advantaged by the more suitable or cheapest services offered by the new phone operator, without advising his contacts of a new telephone number. It might also happen that the portability is only about the services on which a customer is subscribed. For instance, a customer might move from an European Country to another for a limited period, e.g., one year, but keeping his subscription, even with a new phone number, with the company and using the same services already available but not by roaming. At the end of such period, the customer could move back to his home country again, picking up his original telephone number and subscription. Starting from this description of the case study, we could identify the following stakeholders:

• Cell Phone Operators (CPOs)
• Customers

Business Goals and Domain Assumptions

Business Goals and the Domain Assumptions define the functionalities and the properties of both the machines and the environment where the systems operate. Whereas the business goals state the functionalities of the product, the domain assumptions report properties or restrictions of the system.

Business Goals

Table BG1. Business Goal TELCO-BG1

Field	Description
UniqueID	TELCO-BG1
Short Name	To provide mobile phone number portability
Type	Business Goals.
Description	The system shall offer some capabilities to permit the portability of a mobile phone number across different CPOs. Service portability makes possible to the customers change the telephone operator keeping their old phone numbers. The customer could decide to move to a certain CPO, since the charges it has for a particular service are more convenient for him. The customer would avoid to have a new telephone number, since he should have to notify all his contacts of the changed number.
Rationale	Satisfy the need of a customer that want to take advantage of the services of a certain CPO without change his old telephone number.
Involved Stakeholders	CPOs and customer
Conflicts	None
Supporting Material
Priority of accomplishment	Must have.

Table BG2. Business Goal TELCO-BG2

Field	Description
UniqueID	TELCO-BG2
Short Name	To provide mobile phone number portability
Type	Business Goals.
Description	The system shall enable a customer moved to another country to use the service already subscribed in the former country. Maybe not all services are available, but services could be composed by existing ones or even, if no other options are available, the customer could be linked to his home country for this service (with an extra-fee).
Rationale	Satisfy the need of a customer that want to take advantage of the services of a certain CPO when moving in the countries where CPO operates.
Involved Stakeholders	CPOs and customer
Conflicts	None
Supporting Material
Priority of accomplishment	Must have.

Table BG3. Business Goal TELCO-BG3

Field	Description
UniqueID	TELCO-BG3
Short Name	To satisfy national and european rules
Type	Business Goals.
Description	European and National governments strictly regulate some of the services provided by the CPO. As a consequence, several regulations had been approved especially for making the change of a mobile operator as simple and economic as possible. Since these rules change during the time, the system should be able to promptly react.
Rationale	Enable a quick reaction in case of new European and National regulations.
Involved Stakeholders	CPO
Conflicts	None
Supporting Material
Priority of accomplishment	Must have.

Table BG4. Business Goal TELCO-BG4

Field	Description
UniqueID	TELCO-BG4
Short Name	To make the portability as much transparent as possible to the customer
Type	Business Goals.
Description	To improve the customer satisfaction the portability of services and numbers should be transparent to the user. As a consequence, the user can interact either directly to the system by a Web application or supported by a company employee to apply for the number portability. The customer should realize that the number portability occurred only at the end of the process. Only in case of problems, the customer will be contacted.
Rationale	To improve the customer satisfaction
Involved Stakeholders	CPOs and customer
Conflicts	None
Supporting Material
Priority of accomplishment	Should have.

Table BG2. Business Goal TELCO-BG5

Field	Description
UniqueID	TELCO-BG5
Short Name	To provide new added-valuee services
Type	Business Goals.
Description	The system shall enable CPOs to easily provide new services. Mainly regarding on the evolution of the Web and the spread of new application under the 2.0 umbrella, CPOs need to increase the number of services by considering all the users that consume this kind of applications.
Rationale	Increase the market rate.
Involved Stakeholders	CPOs and customer
Conflicts	None
Supporting Material
Priority of accomplishment	Should have.

Domain Assumptions

Table DA1. Assumption TELCO-S-DA1

Field	Description
UniqueID	TELCO-S-DA1
Short Name	Distributed companies
Type	Domain assumption
Description	The CPO consists of multiple departments, possibly spread over multiple nations. In-house Services are shared among departments: e.g., CRM, Billing, and so on.
Rationale
Involved Stakeholders	CPO
Conflicts	None
Supporting Material
Priority of accomplishment	Must have.

Table DA2. Assumption TELCO-S-DA2

Field	Description
UniqueID	TELCO-S-DA2
Short Name	Service provisioning
Type	Domain assumption
Description	The system shall provide some useful services the customer could access. After an authentication phase the customer should access to personal data and get information about the contracts, the billing and so on. He could decide to change his contract choosing a more suitable telephone charges, or he could have a service to pay the billings.
Rationale	Make available services to the customers.
Involved Stakeholders	CPO and customers
Conflicts	None
Supporting Material
Priority of accomplishment	Must have.

Domain Analysis

Strategic Dependency Model and Context Diagram

The figure below illustrates the strategic dependency diagram of the case study. The diagram puts in evidence the business goals (the ellipses in the diagram) shared among the actors (the yellow circles in the diagram) of the scenario, showing the dependencies among them. The CPOs offer their services satisfying the national and the european rules; their goal is the provisioning of services useful to the customers in order to get information about the status of their contracts and/or to change them. In particular the current case study focuses on the provisioning of the telephone number portability service; such service should be offered to the customer in a transparent way.

Figure below illustrates the context diagram of the current case study. In the context diagram, all the actors that appear in the business goals and scenarios are agents.

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Domain Model

Figure below illustrates the domain model of the current case study. A UML notation is used to represent the entities and the actors involved in the case study and the relationships among them. The CPO stipulates a Contract with a Customer. A contract is characterized by the particular Fares to pay for the service usage; it could include the basic Voice Service or some additional service (Value Added Service) provided by the CPO, such as e-mail services, SMS services and so on. When a Customer requires a Telephone Number Portability of his telephone number moving from a CPO to another one, such portability is associated to a contract. Moreover, the diagram illustrates the possibility of a Customer to access to different type of Services provided by the CPO.

And I thought I was the sensible one. Thanks for setting me staright.