Since the IP telephony Cookbook is a technical reference document, it must include guidelines for users who do not want to read the whole document in order to find the information they need. In this section we give the reader tips on how to read the document in order to retrieve the information needed as fast as possible; for a detailed overview of the contents of the Cookbook, please refer to the previous section. To speed up the information retrieval process each reader should identify himself as belonging to one of the following three groups:

Readers belonging to the first group should, first of all, refer to Chapter 2 to acquire the necessary background to understand the rest of the Cookbook. Additionally, readers who are interested in setting up an IP telephony service should read Chapter 3 to have a clear picture of the possible scenarios offered by the IP telephony and target on the one best suited to their environment needs. The second group of readers may skip the previously mentioned chapters, but Chapter 3 may be of some interest to them; the main focus of this group of users is more likely to be in Chapter 4 and Chapter 5 which give tips and help in setting up an operative service. The third group of users is likely to be more interested in the "value added" services available nowadays with IP telephony (Chapter 6) or in the integration problem of an IP telephony architecture widely distributed across multiple sites and organizations (Chapter 7). All three groups of users may find useful information in Chapter 8 and european project information in Annex A. Last but not least, the list of products and testing experience reported in Annex A is a must for all users who do not want to risk making the wrong choices in a buying decision.