Wireless local area network with roaming indicating multiple communication ranges

A method of operating a local area network including at least one mobile unit and a plurality of access point units, the access point units being connected to each other, the method comprising the steps of:

• the mobile unit receiving at least one transmission from at least one of the access point units, the at least one transmission including information indicative of which of the access point units are within radio range of the mobile unit, the at least one transmission not being solicited by the mobile unit;
• storing the information indicative of which access point units are within radio range of the mobile unit, wherein there are at least three values indicative of radio range:
• one indicating that the associated access point unit is likely to be "near" the mobile unit, one indicating that the associated access point unit is likely to be "far" from the mobile unit, and one indicating that the radio range between the associated access point unit and the mobile unit is "unknown";
• and
• the mobile unit establishing communication with the second access point unit using the stored information indicative of which access point units are within radio range of the mobile unit.