equency hopping patterns of the two piconets are determined by different master device MAC addresses, they are not coordinated and there will be random data packet collisions when the same frequency is Wireless PAN Standards Table 10-5: Example of a Bluetooth PAN (Piconet) and Associated Profiles Device Master/Slave Profile Laptop computer Master Printer Slave Serial port profile Slave Synchronisation profile Laptop computer Slave File transfer profile Mobile phone Slave Dial-up networking profile chosen. However, this will occur very infrequently (statistically once in every 79 X 79 = 6241 data packets) and SO will not significantly affect data throughput. Bluetooth Usage Examples To give an idea of the way Bluetooth is used in practice it is useful to look at the steps involved in setting up a number of connections representing different profile usage. Synchronising a PDA over Bluetooth The steps in setting up this service, which uses the serial port and synchronisation profiles, are shown in Table 10-6. Table 10-6: Usage Model - PDA Synchronisation Description Pair the two devices (PDA and desktop or laptop), exchanging PIN/passkey. Use installed Bluetooth software on the host desktop/laptop to associate the incoming Bluetooth serial port with a specific COM port (e.g. COM3). Security of the link (encryption) will usually be specified in this step, and automatic synchronisation on connection may also be specified. Use synchronisation software on host desktop/laptop (e.g. Microsoft ActiveSync) to identify the serial port for synchronisation with the COM port specified in Step (2). Establish a connection with the host desktop/laptop from the PDA. Initiate synchronisation, unless automatic synchronisation on connection was selected at Step (2). Chapter Ten Internet connection from a PDA over Bluetooth The steps in setting up this service, which uses the LAN access profile, are shown in Table 10-7. Table 10-7: Usage Model - Internet Connection from a PDA Description Pair the two devices (PDA and desktop or laptop)