in the same frequency band, the Bluetooth radio typically hops faster and uses shorter packets. This makes the Bluetooth radio more robust than other systems. Understanding Changing Telecommunications - Building a Successful Telecom Business CREATING A PICONET Slave 3 Slave 2 Master Slave 1 Figure 13.42 Example of a piconet Interoperability with other Bluetooth-capable devices is supported by means of pro- files, indicating what functionality a device supports. Devices with the same profiles can communicate. Bluetooth can also be used for the creation of ad hoc networks. Let us take piconet as an example. See Figure 13.42. A Piconet is a collection of devices connected via Bluetooth technology in an ad hoc fashion. A piconet starts with two connected devices, such as a portable PC and cellular phone, and may grow to eight connected devices. All Bluetooth devices are peer units and have identical implementations. However, when establishing a piconet, one unit will act as a master and the other(s) as slave(s) for the duration of the piconet connection. Several piconets can be established and linked together ad hoc, where each piconet is identified by a different frequency hopping sequence. All users participating on the same piconet are synchronized to this hopping sequence. The topology can best be described as a multiple piconet structure. Control Network 14.1 INTRODUCTION In Chapters 11, 12 and 13 we reviewed traffic resources. We now need to understand how to control and use them in order to create a successful business. The services develop towards multimedia handling. The control layer responds with the intelligence of an IP multimedia subsystem and deployment of more advanced control network signaling, mainly based on the SIP protocol. An introduction to the subject of control was included in Chapter 3 (See section 3.2.1). The control network cooperates with the service layer, subscriber equipment and with other networks, in order to create adequate end-to-end connections in the connectivity layer. The coope