Co-channel interference (and airtime)
termnetworkingIT support
The throughput loss that occurs when neighbouring access points share a channel: they do not corrupt each other's transmissions, they defer to them, so the available airtime is divided rather than added.
It is the most misdiagnosed wireless problem, because every signal indicator looks excellent while measured throughput collapses - and the usual response, adding more access points, is what caused it. The related trap is that the slowest client sets the pace: a device at a low data rate occupies the channel far longer to send the same bytes, so one distant laptop can consume the airtime a dozen nearby ones would have shared. Design for capacity means more radios at lower power on planned channels, not stronger signal.
Also known as: cci, airtime utilisation, channel contention, too many access points