![]() ![]() I used to think, “Well, once we get to the next major release they will have all this fixed.” That was many years ago. Managers often don’t believe what their wireless engineers tell them about the shoddy state of the code they are running on networks that support patient care in hospitals and critical factory production lines, but it is a very real problem. And yet they are, frequently, as if no quality assurance or beta testing is ever done on the code that so many mission critical WLAN’s rely on. If you have worked with Wi-Fi long enough, you have a favorite facepalm-inducing example of an access point bug that should never have been allowed out into the wild. This major problem will remain unresolved for as far as I can see into the future. Because the IEEE decided these features are optional, and the Wi-Fi Alliance does not require their support for certification, we will never be able to fix roaming this way. What a client actually does with 802.11k neighbor reports is anyone’s guess because they are absorbed into their already flawed, proprietary roaming algorithms, and how and when AP’s use BSS transition frames is largely undocumented). AP vendors let you enable or disable these features, but give little insight into how they will actually behave (e.g. Unfortunately, client support for 802.11k is limited and support for beacon reports is even more limited. This is similar to the method LTE uses for handoffs (roaming in cellular-speak). The WLAN administrator could configure whatever RSSI or MCS threshold was appropriate for the WLAN as designed, and all clients would roam in accordance with it. The AP could then use 802.11v BSS transition frames to direct clients to roam to the appropriate AP at the appropriate RSSI or MCS threshold. With 802.11k beacon reports, all clients could periodically report their RSSI and the RSSI of nearby AP’s to the AP. I believe that the right combination of 802.11k and 802.11v features could fix the sticky client problem. It’s the wild west, anything goes, and you don’t know what you are getting until you take a client out of the box and test it yourself.Īnd yet, the tools to fix the situation already exist. There have been engineering efforts at IEEE to improve roaming, but very little has come of it, and the Wi-Fi Alliance does not test that clients roam effectively in its certification programs. Yes, some manufacturers have published roaming specs, but they are not telling the whole story, and real-world observations often contradict their documentation. Further, most clients provide zero visibility into their roaming algorithm, let alone provide any configuration to correct it. Some are so sticky that they are totally unusable in a multi-AP network unless they never move. Very, very few Wi-Fi clients roam effectively. ![]() This is mostly a client problem in Wi-Fi, but it deserves a callout all its own. I could go on… but why beat a dead horse? Bad Roaming ![]() But so many Wi-Fi clients are utter garbage! They lack support for enterprise security (WPA2/3-Enterprise), some only support the enterprise-unfriendly 2.4 GHz band, there are new clients on the market today with 802.11g radios in them, their drivers are buggy and often go unpatched, and few clients support amendments to the 802.11 standard that are important to enterprise Wi-Fi performance and security (802.11k/v/r/w). Much has been written about the sorry state of Wi-Fi clients, so I won’t go too far into what is already well-documented. These are the real problems that real enterprises have with Wi-Fi, and each successive generation of Wi-Fi has does little to address them. Please bear with me as I go through my list of gripes. Today I’m going to channel my inner Lee Badman and get a little grumpy about Wi-Fi. They could be fixed, other wireless protocols have solutions for some of them, and there have been attempts to fix them but the results are so watered-down that they are ineffective. No technology is perfect, but for most of my career in Wi-Fi there has been a persistent set of problems that continue to have no resolution in sight.
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