aining fields involve flow control also be considered a way to virtually increase the (handshaking), error detection and sequencing. Since the network's capacity from eight devices to 255, or even header has prime importance in the packet, it is endowed more. When entering park mode, a slave gives up its with forward-error correction having a redundancy of times three. active piconet address and receives an 8-bit parked member address. It goes into low-power mode but wakes Following the header in the packet is the payload, which up from time to time to listen to the traffic and maintain contains the actual application or control data being transferred between Bluetooth devices. The contents of synchronization. The master sends beacon transmissions periodically to keep the network active. Broadcast the payload field depend on whether the link is an ACL or transmissions to all parked devices can be used to invite SCO. The payload of ACL links has a payload header field any of them to rejoin the network. Parked units them- that specifies the number of data bytes and also has selves can request re-association with the active network a handshaking bit for data-buffering control. A CRC (cyclic by way of messages sent during an access window that redundancy check) field is included for data integrity. As occurs a set time after what is called a "beacon instant." A stated above, SCO links don't retransmit packets SO they polling technique is used to prevent collisions. don't include a CRC. They don't need a header either because the SCO payload has a constant length. The previous packet description covers packets used Packet format to transfer user data, but other types of packets exist. For example, the minimum length packet contains only the In addition to the data that originates in the high-level access code, without the four-bit trailer, for a total of application software, Bluetooth packets contain fields of 68 bits. It's used in the inquiry and paging procedures for bits that are created in the baseband hardware o