Wireless users facing issue range issue between two ssid

[Puneet Gupta]

Hi

It has been observed  users aren’t able to be connect to CORP SSID  however they are able to connect the GUEST SSID at the same time. Incase user is moved more towards the AP then he is able to connect to CORP SSID.

Also observed that CORP SSID is showing less signal as compared to guest SSID at same location.

Please help.

Thanks

Puneet

[George Stefanick]

I assume both ssids are being broadcasted from the same ap ? Of so the signal is being tx'd at the same power level from the radio.

My guess is its your client. Can you replicate this with other devices ?

Sent from Cisco Technical Support iPhone App

[Puneet Gupta]

Hi

Thanks for the reply...

Actually broadcast option is disabled in both SSID.We can clearly see the signal range differance between these two SSID when both are connecting to the saem access point.

Number of clients on corp users are higher than in comparison to guest SSID.This might be the reason.But i am aware of this that number of associated cleints can be 25 on a single access point.

[Sahil Mengi]

Punnet,

Its not about the number of clients on that ap at the moment, though you are right recommendations are of about 24 clients on indoor lap platforms provided RF looks good, otherwise i have seen plannings with 16 per lap.

I think the question George is asking is what is the power level your client is transmitting at and what is the power level of your lap that is in question here?

Default transmit power on lap is 20dbm, 100 mw to give you the actual power value.

Usually clients/ machines transmit at 30mw.

My Questions:

- Which radio does this client connect to, 802.11b/g/n or a/n?

- What is the distance between lap and client when it fails to connect?

- What is the power level for the radio client connects to on that lap? (1 being max and 6 being lowest)

- Do you have lower data rates of 1 and 2 Mbps enabled on wlc?

  - If yes can we try disabling them, this will improve capacity though at the cost of reduced service area for that lap.

Regards

Sahil

[Puneet Gupta]

Hi Sahil

Right now i don't have these information and will get back to you but for a better piture,i want to provide you some inputs ..

the same client is able to connect GUEST SSID at one particular location but not able to connect CORP SSID.

I can see the signal strenghth is showing lower(Four Signals) in comparison to GUEST SSID(6 Signals).This is happening for every machine.

Both SSID ae configured in the same way except the authentication method.

[Leo Laohoo]

I can see the signal strenghth is showing lower(Four Signals) in comparison to GUEST SSID(6 Signals).This is happening for every machine.

Do you have one WAP broadcasting both SSID or are you using different WAPs?

Is this issue happening to ONE/SOME/ALL user(s)?

What kind of WAP are you using?

[Puneet Gupta]

Hi

We have number of access points installed Model Cisco 3501.We have observed this issue at one floor only.

Controller Model---Cisco5508

AP Model------------3500 Series

Contrlloer version--7.0.98.0

[Leo Laohoo]

I think I know what's going on.

The client is choosing the wrong WAP to join.  Let me explain.

You have, say three floors with WAP.  The client is on the second floor.  Instead of choosing a WAP in the second floor the client is choosing to join a WAP in the third or first floor.  This is why you have different RSSI readings per SSID.

One way to correct is to ensure that TPC and DCA is set to automatic.  You also may want to disable 802.11b data rates.

And another thing ... 7.0.98.0?????  You're still stuck with this?  Seriously?  You may want to consider looking into 7.4.100.0 or 7.3.101.X. 

[Puneet Gupta]

Hi

Thanks for the reply.I will ask client to upgarde the code in WLC.

Actually we have one access point insatlled on that floor (Basement) and other access point is installed at second floor.

I am able to connect the GUEST SSID at that location but not able to connect the CORP SSID at the same time at the same location and this is tested many times.

Can you help me in suggesting, how can i disable the 802.11b data rates

(WLC GUI >> Wireless >> 802.11 B/G/N >> Network >> Disable 802.11B/G network setup)

in WLC and what is benefit of this  ?

what will happen to the B/G Clients when they will try to conect with WAP. after disabling the b/g ?

[Sahil Mengi · Accepted solution]

The default rates with 802.11b are 1 and 2 Mbps and supported ones include 5.5 and 11 being the max.

You can disable 1 and 2 Mbps here.

(Do not uncheck 802.11 b/g box, but disable the b rates)

- This will improve the capacity as well as reduce the effective service area.

  - This way any RF bleeding between the floors should reduce and as Leo has hinted should help client selecting lap on the same floor.

- Another benefit, if any client at the cell edge on lower data rates/power is missing an ack from AP resulting in layer two retransmisions for that client, as in case of a hidden node, that would be rectified.

Regards

Sahil

[Puneet Gupta]

Thanks

Biu i want to understand ,why it will reduce the effecive service area after disabling the 802.11b clients ?

[Scott Fella · Accepted solution]

Because you are not allowing those rates... the lower the rates, the further the signal... you really don't want your clients connecting at 1mbps.  Disabling the lower rates keep a smaller cell but enhances the roaming in a way.  Clients may keep their association to an ap until it drops from 1mbps.  

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Scott Fella · Accepted solution]

Reference this table:

http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7925g/7_0/english/administration/guide/7925wrnt.html#wp1153010

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Scott Fella]

Another good example:

http://www.cisco.com/en/US/docs/solutions/Enterprise/Mobility/emob41dg/ch3_WLAN.html#wp1000295

Thanks,

Scott

Help out other by using the rating system and marking answered questions as "Answered"

[Puneet Gupta]

hi

thanks a lot..it is really helpful.