Wi-Fi network roaming with 802.11k, 802.11r, and 802.11v on iOS

Learn how iOS and iPadOS improves client roaming using Wi-Fi network standards.

iOS supports optimized client roaming on enterprise Wi-Fi networks. The 802.11 Working Group standards k, r, and v let clients roam more seamlessly from access point (AP) to AP within the same network.

802.11k

The 802.11k standard helps devices search quickly for nearby APs that are available as roaming targets by creating an optimized list of channels. When the signal strength of the current AP weakens, your device will scan for target APs from this list.

802.11r

When your device roams from one AP to another on the same network, 802.11r uses a feature called Fast Basic Service Set Transition (FT) to authenticate more quickly. FT works with both preshared key (PSK) and 802.1X authentication methods.

iOS 10 and later and iPadOS include support for adaptive 802.11r on Cisco wireless networks. Adaptive 802.11r offers FT without the need to enable 802.11r on the configured Cisco wireless network.

802.11v

iOS and iPadOS support these 802.11v functionalities on certain devices:

  • Basic Service Set (BSS) transition management
  • Disassociation Imminent
  • Directed Multicast Service (DMS)
  • BSS Max Idle Service

BSS transition management with Disassociation Imminent allows the network’s control layer to influence client roaming behavior by providing it the load information of nearby access points. The device takes this information into account when deciding among the possible roam targets.

DMS optimizes multicast traffic transmission on wireless networks. The device uses this information to enhance multicast communication and preserve device battery life.

The BSS Max Idle Service helps clients and access points efficiently decide how long to remain associated when no traffic is being transmitted. The device uses this information to preserve device battery life.

When you combine 802.11k and 802.11v’s ability to speed up the search for the best target AP with FT's faster AP association, apps can perform faster and you get a better Wi-Fi experience in iOS and iPadOS.


Learn more

Most Wi-Fi network hardware vendors support 802.11k, 802.11v, and 802.11r (FT). You need to enable and configure these features on your Wi-Fi router before your network can use them. Setup varies, so check your Wi-Fi router's manual for details.

The lists below show which iOS devices support 802.11k, 802.11r, and 802.11v. To use 802.11k and 802.11r, you need iOS 6 or later. To use 802.11v, you need iOS 7 or later. To use adaptive 802.11r, you need iOS 10 or later.

802.11k and r

  • iPhone 4s and later
  • iPad Pro and later
  • iPad Air and later
  • iPad mini and later
  • iPad (3rd generation) and later
  • iPod touch (5th generation) and later

Adaptive 802.11r

  • iPhone 6s and later
  • iPad Pro and later
  • iPad (5th generation) and later

802.11v

  • iPhone 5c, iPhone 5s, and later
  • iPad Pro and later
  • iPad Air and later
  • iPad mini 2 and later
  • iPad (5th generation) and later
  • iPod touch (6th generation) and later

Pairwise master key identifier caching

iOS 5.1 and later and iPadOS also support pairwise master key identifier (PMKID) caching. You can use PMKID caching with some Cisco equipment to improve roaming between APs. Sticky key caching (SKC) is a form of PMKID caching. SKC is not equivalent to, nor compatible with, opportunistic key caching (OKC).

To support adaptive 802.11r, the Cisco network must be using controller code version 8.3 or later. 802.11w's protected management frames (PMF) interoperate with iOS and iPadOS support for 802.11k, 802.11r, and 802.11v.

Learn about how devices running iOS and iPadOS roam in an enterprise Wi-Fi environment.

Learn more about these standards from the IEEE website:

Learn how to identify these device models:

 

Information about products not manufactured by Apple, or independent websites not controlled or tested by Apple, is provided without recommendation or endorsement. Apple assumes no responsibility with regard to the selection, performance, or use of third-party websites or products. Apple makes no representations regarding third-party website accuracy or reliability. Risks are inherent in the use of the Internet. Contact the vendor for additional information. Other company and product names may be trademarks of their respective owners.

Published Date: