Handover in a wireless local area network (wlan)

A method for determining the transfer by a unit of transmission / reception, a set of current basic services, BSS in a wireless local area network, WLAN, comprising: determining (S42) a requirement class higher service traffic and quality of service, QoS of that highest class of a mark BSS, that class of traffic service being associated with an upper threshold of the intensity of the received signal and / or signal to noise ratio, RSS / SNRmax, and a lower threshold of received signal strength and / or signal to noise ratio, RSS / SNR min; compare the intensity of the received signal current and / or signal to noise ratio, RSS / SNR max, and complete the transfer if the RSS / SNR exceeds current RSS / SNR max; if the RSS / current SNR is not above RSS / SNR max, then compared the RSS / current SNR with RSS / SNR min, and the following steps are performed if the RSS / SNR is greater than or equal to RSS / SNRmin get (S56) the channel utilization rate and frame loss of a load element QBSS provided at the mark; get (S58) the QoS parameter set and the average delay in a current BSS contained in the beacon; calculating (S60) one QoS index using a list of QoS parameters including one: 1: or over channel utilization, the rate of frame loss and the average delay of the current BSS, and wherein the step of calculating the QoS index further comprises: setting (S90) a QoS index to zero (0); creating (S92) a list of QoS parameters; selecting (S94) one of the QoS parameters; comparing (S96, S100) the selected QoS parameter with a threshold higher QoS and QoS lower threshold that QoS parameter; increasing (S98) the QoS index when the selected QoS parameter is greater than the upper threshold QoS parameter of the QoS; reducing (S102) the QoS index when the QoS parameter is less than the lower threshold of QoS for that parameter; and leaving the QoS unchanged when the selected QoS parameter is not greater than the upper threshold of QoS and is not less than the lower threshold of QoS parameter of the QoS; and terminate the transfer and retaining communication with the current BSS when the calculated QoS index is at least equal to a threshold corresponding to the QoS requirement QoS index.