Smartphones & tablets vs. Laptops on a Netvanta 150s wireless network

[Anonymous]

We are servicing a Hotel with a wireless network utilizing NetVanta 150 access points which are controlled via NetVanta 1238P switches.  The customer has noted that users cannot connect reliably with smartphones and tablets while laptops have few, if any, issues connecting.  The network is an open netowrk and internet access is allowed by a ZyXel gateway which grants access through a splash page.   The problem is not with the ZyXel as any user getting to the splash page are able to enter their password and gain access to the internet.  The problem is the initial connection to the access point.  The signal strength at the device shows adequate signal but despite the open network configuration, they are not able to connect to the AP.  In rare instances they are able to connect but are dropped within 30 seconds or so.  What are the possible issues here?  Thoughts?

Sample AP confg:

!

interface dot11ap 1 ap-type nv150

  access-point mac-address 00:A0:C8:65:FF:B4

  name AP3-1

  location AP3-1

  ip address 10.30.0.35 255.255.0.0

  ip default-gateway 10.30.0.1

  event-history on

  event-history priority 6

!

!

interface dot11ap 1/1 radio-type 802.11bg

  channel 11

  no shutdown

!

!

interface dot11ap 1/1.1

  description Wiz_802.11BG_VAP

  ssid broadcast-mode "Hotel"

  security mode none

  no shutdown

!

!

interface dot11ap 1/2 radio-type 802.11a

  no shutdown

!

!

interface dot11ap 1/2.1

  description Wiz_802.11A_VAP

  ssid broadcast-mode "Hotel" 

  security mode none

  no shutdown

!

Thank you,

Dan

[Anonymous]

:

Thank you for asking this question in the support community.  Do you know what firmware version the ADTRAN switch is running?  How many ADTRAN APs are controlled by the switch?  It appears the wireless subnet is a /16 subnet.  Approximately, how many users do they have at any given time?  Do they only experience the issue during times of high usage? 

As far as the ADTRAN is concerned there should be no difference between  PCs and smartphones/tablets.

Levi

[Anonymous]

Levi,

We have 3 switches supporting the Netvanta 150 access points.  All three switches are 1238Ps.

The first two 1238Ps (hostname 1238-2 and 1238-3) are running 18.01.04.

The last 1238P (hostname 1238-5) is running 18.01.01.

We have some 1234Ps in the network as well.

Yes, the guest network has been addressed as a /16.

The ZyXel VSG-1200 is the internet gateway and had never reported over 20 users throughout the property at any time.  During our tests with the hotel staff there were 8 users with DHCP leases.  It is a new property and has not seen any record breaking occupancy numbers.  The problem happens with very few users on the network.

We didn't want to confuse the matter with too many variables so we have been focusing on the lobby access point for our tests.  The access point in the lobby is AP1-5 and it is connected to port 29 of 1238-2.  While the staff has been using this AP for testing other users throughout the hotel have mentioned the same issues between laptops and phones.

To eliminate a firmware issue I'd like all the switches to be running the same version.  What version of firmware should I use to upgrade these switches?

Dan

[Anonymous]

:

If all the NV123x Series switches are first generation, then I recommend running the latest firmware for those products, which is 18.01.04.  Furthermore, I recommend against having a /16 subnet, as there are little benefits compared to the downsides of such a large subnet.

Do you know if the phones/tablets that are having the issues are a certain manufacturer?  I also recommend against having an "open" wireless security mode.  Have you tried incorporating a security mode for the wireless to see if that alleviates the issues?  Even if you have a password of "1234" that is often better than "open."  I have seen in the past where some manufacturers have trouble working with "open" security.

Levi

[Anonymous]

Levi,

All the "wireless controller" switches are first gen switches.  Two of the 1238Ps are running 18.01.04.00 and one is running 18.01.01.00.  I will upgrade the 18.01.01 switch tonight.

It should be noted that the 1234Ps are all running XB.01.00 but none of them are wireless controllers

While I understand your point regarding the /16 subnet and the few benefits it provides.  I cannot see how that would come into play with our current issue.  There have never been more that 20 total wireless users connected throughout the hotel property.  There are 34 Netvanta 150s throughout the property.  Is there some reason to believe that this is contributing to the connection problem?  If so, how?

We have attempted to use Apple iPads, iPhones, Android devices - both phones and tablets.  It doesn't really matter.

I was thinking along the lines of radio strength in the smaller devices but standing next to an access point doesn't change the outcome.

By the request of the property owners we have given instant connection for their guests.   So the security is "open".   Further background: following connection to the AP radio the user is instructed to open a browser and internet access is granted via entering a password on a splash page from a ZyXel VSG-1200 gateway.

I will run a test by placing a WEP security on the access point and update this thread with the results.

Thanks,

Dan

[Anonymous]

:

While I agree that the /16 subnet should have nothing to do with this issue, my recommendation was only an attempt to warn you of the possibility of future issues.

After a brief test with some phones and tablets connecting to first generation NV1238s and NV150s here, I could not reproduce any connection issues.  Have you obtained any debug information on the controller when a unit doesn't connect?  What do the debug dot11 all and debug dot11 client commands produce?  Is the device in the show dot11 clients output, when the device doesn't connect?  Does the device show in the ARP or DHCP tables?  Does it connect to the wireless, but cannot pass traffic?  Is there a time limit before a device that can't connect is able to connect again?

Please, let me know the answers to these questions as well as the results of requiring wireless security on the ADTRAN unit.

Levi

[Anonymous]

:

I marked this post as "assumed answered," but please do not hesitate to reply if you have further questions.

Levi