When the device sends or receives data, it picks target BSSIDs whose RSSI is eight dB or greater than the current BSSID’s RSSI. The difference in signal strength against the current BSSID's RSSI.Whether the client transmits or receives a series of 802.11 data packets.IOS and iPadOS will select target BSSIDs based on: 40 MHz channel width is preferred over 20 MHz.80 MHz channel width is preferred over 40 MHz or 20 MHz.

If multiple 5 GHz SSIDs are scored the same, iOS will choose a network based on the following criteria: Higher score networks offer a better Wi-Fi experience. iOS uses these details along with signal strength measurements (RSSI) to score candidate networks. iOS considers information shared by networks about channel utilisation and quantity of associated clients. This information can help you design a wireless network that supports real-time services, such as voice and video. This can add several seconds to the process.

If you don’t turn on 802.11k, the client has to scan every channel on each band to find a roam target. It immediately scans those channels, finds that the AP on a channel has the appropriate signal strength and roams. If it uses the neighbour report that 802.11k provides, it finds APs that support the current ESSID on three channels. When the device crosses the -70 dBm threshold, it scans for roam targets. This can add several seconds to the discovery process.įor example, a user who is on a call may walk to the other side of the building. If you don’t turn on 802.11k, iOS has to scan more methodically. This helps because iPhone, iPad and iPod touch use the first six entries in the neighbour report and reviews them to prioritise its scans. The roam scan runs more quickly if you turn on 802.11k on your control plane. The stations check all available channels in either the 2.4 GHz band or the 5 GHz band. This is when stations check for access points (APs) that support the current ESSID.

Ipad wifi channel scanner