System selection is critical, and once the user engages a supplier, it is difficult to transfer to another even in those cases where industry standards are in effect. De facto or proprietary standards reign. FHSS is a narrowband carrier with changing patterns of transmission that are recognized by both receivers and transmitters. When the two devices are in synch, they produce one logical communications channel. DSSS produces bit patterns called chips or chipping codes.
Reliability is based on the length of the chipping code or on how many bits of data it carries.
Because an error-correcting function is built into radios, it is often not necessary to retransmit data, thus improving performance. Some software and hardware suppliers provide home-networking solutions via a wireless LAN, using the home's PC as the central control element. The figure below illustrates a wireless home LAN configuration in which one PC acts as a master to the network. It provides network addressing and routing between the home and the Internet. This straightforward approach simply marries familiar PC technology to new home-networking technology.