Research, development and trades concerning the powerful Proxmark3 device.
Remember; sharing is caring. Bring something back to the community.
"Learn the tools of the trade the hard way." +Fravia
You are not logged in.
Time changes and with it the technology
Proxmark3 @ discord
Users of this forum, please be aware that information stored on this site is not private.
Pages: 1
Hi Everyone,
I have a problem with my HID products, We have HID Tags / cards for our tenancy floors and so dose the base building. We also have gold class readers.
The problem is when both cards are together they cancel each other out, we would have like to stick HID tags on the back of the base building passes, but the tags don't work,
so we had to go with FOB keys hanging off the base building cards.
Would really appreciate your feedback.
Daniel.
Offline
Sounds like you're putting two 13.56MHz cards together. Can you take a photo of the two cards?
Offline
Hi Oxffff,
Can not see anything to attach the file.
Offline
Go to somewhere like tinypic and upload the photo there. Post the link here.
Offline
Try this
Offline
Tag collision in RFID systems happens when multiple tags are energized by the RFID tag reader simultaneously, and reflect their respective signals back to the reader at the same time.
Both tag and card are working at the same frequency : 13.56 MHz
When you present the card/tag to the reader at the same time, the reader :
- sends the signal to either card or tag.
- sends the signal and both tag + card answer.
- or everything is mixed up and the reader cannot distinguish between the 2...
You need to isolate tag and card. I heard many stories on "how to block RFID signal" I haven't try any methods. Would be interested to know if you can put some "isolant" between card and tag.
They usually put that 13.56 MHz tag/sticker you have on top of a 125 KHz card so it doesn't interfere between each other...
Last edited by o0o0o0o (2013-07-18 09:13:29)
Offline
The HID iClass credentials use an IDIC chip called PicoPass (manufactured by Inside Secure) to support the identification function and communication with the reader. http://www.insidesecure.com/eng/Product … s/PicoPass
This chip does employ an anti-collision mechanism such that multiple credentials can communicate their ID to a reader when they are grouped close together. It can usually take several seconds to gather the data from a credential if it is in close proximity to another tag.
I just tried several groups of iclass cards and my iclass reader was able to read them correctly when they were positioned back to back.
I also tried reading multiple keyfobs when they were close together in pairs. For some unknown reason the iclass reader could not read those at all. The only difference between the two types of credentials should just be the size of the antenna so I personally don't understand why cards would work but the fobs would not. It sounds like a question that you should ask your Gold Class supplier (ISCS) or HID directly.
Offline
Thanks guys, really appreciate your feedback.
Offline
Pages: 1