Pattern-Oriented Software Architecture Volume 3: Patterns for Resource Management

7 Case Study: Mobile Network

“I have always wished that my computer would be as easy to use as my telephone. My wish has come true. I no longer know how to use my telephone.”

Bjarne Stroustrup

This chapter describes a domain-specific example and shows how the patterns presented in Chapter 2, Resource Acquisition, Chapter 3, Resource Lifecycle, and Chapter 4, Resource Release, can be applied to the resource management requirements of a domain. The example presented is a telecommunications system for mobile phones. As described in Chapter 5, we follow the steps by first identifying the hot spots in the system. Since there is a close relationship between the hot spots and the forces that must be resolved, we apply the resource management pattern language to directly address the forces.

This chapter first presents an overview of some of the key concepts of the domain. It then goes into details and tries to identify the forces specific to the domain that need to be addressed. Using the patterns presented in the previous chapters, the forces are addressed and a solution presented using the resource management pattern language.

7.1 Overview

A mobile network includes all the network elements necessary to accept a call from a mobile phone and forward the call to the core telecommunication network.

The protocols and the deployment of responsibilities among the network elements involved are defined by the Universal Mobile Telecommunications System (UMTS) standard [3GPP04], sometimes also ...