The best practices for WLANs also includes deploying highly-available WLCs, in conjunction with high-density of access points to promote always-available WLAN infrastructure. In addition, Cisco’s HDX suite of technologies such as Cisco CleanAir, ClientLink, Optimized Roaming, and Radio Resource Management automatically allows to optimize your network performance while simultaneously reducing coverage holes and bypassing interference.
Recommendations for Apple Devices on Cisco WLAN are summarized as follows:
- Cisco recommends a 5 GHz only network and coverage design for all apple devices. The 5 GHz band is typically less affected by non-802.11 sources of interferences than the 2.4 GHz band
- Cisco recommends closely monitoring the channel utilization provided through the WLC dashboard. High channel utilization values may be an indication of new sources of interference, AP outages, or an influx of new Wi-Fi devices.
- Cisco recommends monitoring for APs changing channels frequently, and take action to resolve identified 5 GHz Wi-Fi channels that are most affected by known sources of interference on a regular basis.
- Cisco recommends all Apple devices to be connected to a WLAN with a QoS value of platinum (Voice) and with WMM set to required. This allows the Ethernet traffic from the AP to connect to the switch port with a QoS value representative of the priority on the Wi-Fi channel.
- Cisco and Apple recommend that you configure an 802.11r mix mode WLAN for fast transition 802.1X or WPA2 PSK capable clients and 802.11r-compatible clients to join the same network
- For high density enterprise environments, Cisco and Apple recommend to use 802.11r with Over the air transition for optimal 11r-FT performance.
- Cisco recommends configuring 802.11k on the WLAN to provide Apple devices with a neighbor list response. Cisco v8.0MR3 and v8.1.120.0 and Apple iOS 8.0 is the minimum version recommended for 802.11k.
- Cisco and Apple recommend the use of 802.11v BSS Transition Management to help balance client load across access points
- Cisco recommends managing data rates to provide the coverage that is suitable for the number of clients needed in the coverage of a channel, with bandwidth needed in the coverage of the channel.
- Cisco recommends for Channel Bonding: use 20 MHz when channel density (e.g., high number of APs in environment) is needed, and consider 40 MHz when client traffic uses heavy bandwidth (e.g., video) and DFS Channels are available.
- Cisco recommends using DSCP 46 for voice traffic based applications, translates to 802.11e – UP 6
- Cisco and Apple recommends a minimum data rate of 12Mbps and 24 Mbps as the mandatory rate as a general best practice for Apple devices on Cisco Wireless LAN. If the 5GHz coverage is marginal, set 6Mbps as the lowest mandatory rate, and make sure that 12 and 24Mbps are enabled as well.
- Cisco highly recommends leaving all MCS rates enabled.
- Cisco recommends that at all times an Apple client device observes a minimum of 2 APs with an RSSI measurement of -67 dBm.
- Cisco recommends monitoring for peer-to-peer communication activity on UNII-3 band channels in a high client density environment. If high number of Apple devices are expected to perform peer-to-peer activity, excluding channels 149, 153 from DCA can be considered as a last resort measure.
- Apple recommends upgrading all devices to the latest iOS 9 or above operating system.
- RF design and monitoring recommendation summary:◦Over all Channel Utilization should be less than 40%.
◦A minimum Signal to Noise Ratio (SNR) of 25 dB.
◦802.11 retransmissions should be kept under 15%.
◦Packet Loss should remain under 1 percent and jitter should be kept to less than 100 ms.
source : Enterprise Best Practices for Apple Devices on Cisco Wireless LAN
