Why there are two Radio interface on my AP ?

[DuJin0509]

Hello ,

My AP 1130 has two Radio interface , 0 and 1, why there are two Radio interface ? what is usefull of this two interfaces ?

If it is correct that one Radio for one ssid ? so my AP can support 2 ssid ?

Thank you .

[hajia]

Hi 

0 is 2.4G

1 is 5G

When you setup a SSID, usually the AP will broadcast both in 2.4G and 5G, so it's 2 radio for one ssid.

And one AP can broadcast more than one ssid, so it's 2 radio for all the ssids.

[DuJin0509]

Thanks Hajia, Then how can I distiguish which frequency my IPAD has connected or will to connect ? 2.4G/HZ or 5G/HZ ? which one does client  prefer ?

[hajia]

Every NIC which supports both 2.4GHz and 5GHz, usually it will prefer 5G.

In WLC, use "show client summary" command, it shows the information you need, for more info, use "show client detail <MAC addess for the device>"

And by default, APPLE device will perfer 5GHz.

[DuJin0509]

Hello , when I excuted "show client summary" on wlc, output as below: ac:fd:ce:38:bf:67 SESLOHUS_AP02 1 Associated 3 Yes 802.11n(5 GHz) 13 No No Export foreign b0:45:19:2a:e6:ce 10.168.130.2 N/A Associated 1 No Mobile 13 No No Export Anchor So this command no only dispaly PC but also AP, right ?

[hajia]

Yes, it will tell you which AP your PC connected to.

[DuJin0509]

Hello , Hajia

This time it does not work , when I execute this command on my vWLC 7.3 , output as below.

(Cisco Controller) >show client summary

Number of Clients................................ 1

MAC Address AP Name Status WLAN/GLAN/RLAN Auth Protocol Port Wired PMIPV6
----------------- ----------------- ------------- -------------- ---- ---------------- ---- ----- ------

0c:48:85:cb:3b:3f AP1 Associated 1 Yes 802.11g 1 No No

I can only see the ap rather than PC's information.

[hajia · Accepted solution]

Sorry I didn't get you.

Cisco Controller) >show client summary

Number of Clients................................ 1

MAC Address AP Name Status WLAN/GLAN/RLAN Auth Protocol Port Wired PMIPV6
----------------- ----------------- ------------- -------------- ---- ---------------- ---- ----- ------

0c:48:85:cb:3b:3f AP1 Associated 1 Yes 802.11g 1 No No

The MAC address should be the PC's MAC.

"AP1" is the AP this PC connect to.

"Associated" means PC has associated to the AP

"1" is the WLAN ID

"YES" means the PC passed the authentication.

"802.11g" means the radio which the PC connected to.

"No" means this is a wireless client.

[DuJin0509]

Thank you Hajia, I got it already , thanks for your answer.

[Sandeep Choudhary]

Hi,

First:

There's a few attributes that are checked to validate which AP a client associates to.  These attributes include: signal strength, transmit power, AP radio channel, AP radio type, number of other clients on the AP, ability of client device radio, type of data client is using (voice, video, etc).  Balancing of clients is then shown on the client diagnostics view in the 'client match' events table on the right hand side, along with reasons why a client is being redirected to another AP (some reason include: sticky client, load balancing, etc).

Second:

You cant force an device to join which band.....but there are always few things which you do to prefer...

I've faced this issue and can say attest that the only way to force a computer to the 5 GHz band is set up the 5 GHz band with a separate name.
Otherwise, the computer will auto connect to 5 GHz if it's close to the access point. At 15-20 feet away depending on obstructions, the computer will connect to 2.4 GHz if you use the same SSID for each band.

Regards

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[DuJin0509]

Thank you for your answer.

[Sandeep Choudhary]

If it is correct that one Radio for one ssid ? so my AP can support 2 ssid ?

NO, Both Radio can support multiple SSIDs(I guess max is 8).

So as Mr./Mrs hajia mentioned,,,,, these are for diff frequency range :

Radio 1 - 5GHz

Radio 0 - 2.4GHz

Here are the channels and freeuncy used with these interfaces: https://en.wikipedia.org/wiki/List_of_WLAN_channels

Regards

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