Forum

Working with a client I was recently asked if a selected vendor supported non-printable characters in the SSID field. It was mentioned that if the null character (00) was prepended to the SSID (ie: 00SSID) the SSID would appear to many clients including WZC as being hidden. Apparently this is due to Windows reading the 00 and recognising this as being the end of the string.

Does anybody know of this or have any information regarding this? The thinking beind it is that you can hide the SSID without actually removing the SSID from the beacon - Supported clients would have no problem connecting to the SSID without the general public accidently trying to connect.

Yes, this works just fine. Many vendors support appending a blank character to the SSID in an AP or WLAN controller. There are also vendors, like FireTide, who use non-ASCII characters calling it an "encrypted" SSID. They only do this between their mesh nodes, so no client utility has to support it. It's not a bad idea really.

Devinator

Thanks for the reply Devin. However im still somewaht confused. I have tried configuring an SSID of "00Flat23" on 2 different APs and simply see this is the SSID from both the WZC and my 3rd party client utility. Any guidance on how I can prove this works?

ah....

I didn't read your post carefully enough. I was talking about a blank (null) character...e.g.

SSID of: Devinator

vs.

SSID of: Devinator_ (where the _ is a blank character).

I haven't tried PREprending in this fashion. Neat concept. I need to try this.

Devinator

continuing on hidding SSID subject. I have my SSID hidden and i read that in the beacons it is transmitted in the clear even when hidden. the thing is that when i went to the Omnipeek personal and check the beacon frame it was hidden instead of having the actual SSID on the clear however it stated the length of it, which i found interesting.

So, am i wrong or what's happening ? Perhaps it is in other management frames or control frames where it is exposed.

thanks
rafael

Rafael,

In fact the beacons are not carrying the SSID when it is hidden or suppressed or cloaked, but a null SSID. The probe requests from someone who knows the SSID from this AP and the probe responses for this client from the AP will contain the SSID in the clear.

Um abra???¡ìo

Regarding the original question from this thread in my understanding the AP or Controller should support configuring the SSID in Hex otherwise there is no way to input a non-ASCII char.