are access point as good as mesh at handoff?

[thiggins]

As far as roaming "hand-offs" go at least some of the responsibility rests on the client device.

No, all roaming decisions are made by the client (STA). APs can attempt to influence the decision by delaying/blocking probe responses, refusing to associate or deauthing (kicking off) devices. But in the end, the STA decides.

11k/v/r are roaming assistance technologies and must be supported by both AP and STA.

Suggested reading:
https://www.smallnetbuilder.com/basics/wireless-basics/33180-how-to-fix-wi-fi-roaming

Deeper dive:
https://www.smallnetbuilder.com/wireless/wireless-features/33195-wi-fi-roaming-secrets-revealed
https://www.smallnetbuilder.com/wir...s/33196-wi-fi-roaming-secrets-revealed-part-2
https://www.smallnetbuilder.com/wir...s/33197-wi-fi-roaming-secrets-revealed-part-3
https://www.smallnetbuilder.com/wir...s/33207-wi-fi-roaming-secrets-revealed-part-4

 

[Trip]

So what is the difference between smartroam and smartroam+?

Per Ruckus documentation of ZoneFlex 9.9 release, when they introduced SmartRoam+:
---------------------------------
To reduce the battery usage, after associating with an Access Point (AP), mobile devices like Apple’s iPhone and iPad do not scan the environment even though the user may have moved far away from originally associated AP. This would result in poor end user experience.

To solve the above mentioned client stickiness issue the SmartRoam feature was introduced wherein the AP would send ‘dis-associate’ frame to client device which will disconnect the client device. This triggers the client device to find better alternate AP.

SmartRoam+ feature of ZF 9.9 further enhances the Ruckus’ SmartRoam in order to provide better quality of experience for the end user. After associating with an AP if user moves far away from initially connected AP, then the AP will send a BSS Transmission message (part of 802.11v) to the client device. This triggers the client device to start the scanning process to find an AP that can provide better service. The client device scans the environment using the filtered AP neighbor list (part of 802.11k) provided by the original AP. While the client device is scanning the environment it continues to stay connected to the original AP.

After client device chooses a specific AP to connect to it uses 802.11r for faster transition by re-using previously-established 802.1x security keys.

Customer Benefits

• Client device roams seamlessly and rapidly
• End user will have higher quality of experience
• Client device saves battery from not having to scan all the APs and channels

https://support.ruckuswireless.com/documents/570-zoneflex-9-9-ga-what-s-new
---------------------------------
So SR+ is adding in elements of 802.11k and 802.11v from packet flow and station-client analytics. Aironet and Aruba have analogous, "secret sauce" approaches to roaming optimization.

 

[coxhaus]

Sounds like smartroam+ is what is required for Apple devices to roam well.

 

[Trip]

Correct. And SR+ has been in all three code bases since 2018 (ZoneDirector, SmartZone and Unleashed). Compatible APs are basically anything from the 7300/7900 series forward, so all R__ series included.

 

[pauljbl]

Is sr+ in unleashed as I though you wasn't sure?

 

[pauljbl]

@Trip
When your roaming between access points what dBm using a WiFi analazer on your phone does it switch between access points?

 

[Trip]

@pauljbl - Using my Samsung Note 5 (Android 7.0), typically in the -65 to -75 dB range, which usually works out pretty well. Video calls never drop a frame; voice calls with ZoiPer don't cut out, either. I'm using two 7982's with a ZD1100 controller on ZoneDirector version 9.10 MR2, Refresh 6 (9.10.2.0.76). And that's with the one remote AP wirelessly backhauled (1-hop mesh). Also, layer 3 tunneling is off (not needed).

 

[ng4ever]

Can the same be said for WiFi extenders ?

 

[Trip]

Can the same be said for WiFi extenders ?

No. Vanilla wifi extenders function only as basic Layer 2 repeaters and cannot propagate the 802.11 amendments required for seamless roaming -- including fast-transition roaming (802.11r), assisted roaming / neighbor lists (802.11k) or network-assistance and power-savings (802.11v). Also excluded, of course, are any proprietary enhancements, such as packet flow intelligence and association management per device (to force roams of sticky clients); Ruckus's "SmartRoam" being an example, or whatever the analogous buzzword would be from other brands (Cisco, Aruba, etc.).

 

[pauljbl]

@Trip
What smartroam settings do you use on your setup?

 

[Trip]

@pauljbl - Here's the output of the Private LAN config that I have SmartRoam enabled on, via show wlan all when SSH'd into my ZoneDirector:
(Pertinent items are FT Roaming and 802.11k neighbor reporting are both on, and SmartRoam is enabled at a level of 3)

NAME = Private LAN
      Tx. Rate of Management Frame(2.4GHz) = 2.0Mbps
      Tx. Rate of Management Frame(5GHz)   = 6.0Mbps
      Beacon Interval = 100ms
      SSID = ***************
      Description =
      Type = Standard Usage
      Authentication = open
      Encryption = wpa-mixed
      Algorithm = aes
      Passphrase = ***********
      FT Roaming = Enabled
      802.11k Neighbor report = Enabled
      Web Authentication = Disabled
      Authentication Server = Disabled
      Called-Station-Id type = wlan-bssid
      Tunnel Mode = Disabled
      Background Scanning = Enabled
      Max. Clients = 100
      Isolation per AP = Disabled
      Isolation across AP = Disabled
      Zero-IT Activation = Disabled
      Priority = High
      Load Balancing = Disabled
      Band Balancing = Disabled
      Dynamic PSK = Disabled
      Rate Limiting Uplink = Disabled
      Rate Limiting Downlink = Disabled
      Auto-Proxy configuration:
        Status = Disabled
      Inactivity Timeout:
          Status = Enabled
          Timeout = 5 Minutes
      VLAN-ID = 1
      Dynamic VLAN = Disabled
      Closed System = Disabled
      Https Redirection = Disabled
      OFDM-Only State = Disabled
      Multicast Filter State = Disabled
      802.11d State = Enabled
      Force DHCP State = Disabled
      Force DHCP Timeout = 10
      DHCP Option82:
          Status = Disabled
          Option82 sub-Option1 = Disabled
          Option82 sub-Option2 = Disabled
          Option82 sub-Option150 = Disabled
          Option82 sub-Option151 = Disabled
      Ignore unauthorized client statistic = Disabled
      STA Info Extraction State = Enabled
      BSS Minrate = Disabled
      Call Admission Control State = Disabled
      PMK Cache Timeout= 720 minutes
      PMK Cache for Reconnect= Enabled
      NAS-ID Type= wlan-bssid
      Roaming Acct-Interim-Update= Disabled
      PAP Message Authenticator = Enabled
      Send EAP-Failure = Disabled
      L2/MAC = No ACLS
      L3/L4/IP Address = No ACLS
      L3/L4/IPv6 Address = No ACLS
      Precedence = Default
      Proxy ARP = Disabled
      Device Policy = No ACLS
      Vlan Pool = No Pools
      Role based Access Control Policy = Disabled
      SmartRoam = Enabled  Roam-factor = 3
      White List = No ACLS
      Application Visibility = disabled
      Apply Policy Group = No_Denys

Per Ruckus's SmartRoam sticky client control guide, a value of "3" is plenty aggressive for me, as I have a Android 7.0+ and Windows 10 Pro environment, which typically roam better by default than Apple stuff, and it works really well for me. YMMV, of course, and if you have Apple devices, you might need to bump that number up to stimulate optimal roam events.