details necessary to determine exactly how this might be calculated or estimated. You might have a directive in your organization to determine if SIP trunking should be deployed, and if yes, how and when-be it for the purposes of technological transforma- tion or cost savings or both. And you might not be convinced these directions or direc- tives are practical or can be implemented. You might simply be grappling with where to start to get some concrete answers that specifically apply to your company. The previous five chapters examine several aspects to consider as you investigate SIP trunking. Chapter 4, "Cost Analysis," provides guidance to compare the costs of imple- menting SIP trunking versus the cost of your current PSTN trunking. Chapter 6, "SIP Trunking Models," Chapter 7, "Design and Implementation Considerations," and, Chapter 8, "Interworking," discuss what SIP trunking might mean to your network design and implementation. Chapter 9, "Questions to Ask of a Service Provider Offering and an SBC Vendor," covers evaluating SIP trunk service providers (SP). This chapter pulls all the detailed information covered in these chapters into the following: An easy-to-use, step-by-step guide to implementing SIP trunking A summary of best practices to follow during the implementation 244 SIP Trunking Deployment Steps Although different deployment steps might be necessary to meet your individual busi- ness needs and may vary from one implementation to another, some typical deployment steps are common. These include Step 1. Plan for migrating to SIP trunking. Step 2. Evaluate available SIP trunk offerings. Step 3. Conduct a Pilot Trial. Step 4. Begin production service. A summary of these steps and the major activities involved in each one is provided in Figure 11-1. Each step is explored in greater depth in the following sections. Planning Evaluation Pilot Production Cost analysis Assess SIP trunk Define clear success Revise the phases Assess traffic provider offerings criteria of production based volumes and Availa