SecurID and garage door openers

[maf at appgate.com]

On 18 okt, Greg Rose wrote:
>>Similarly, how do those garage door openers with "rolling codes" work,
>>given that the user may have pressed the button many times
>>accidentally while out of range of the receiver?
> 
> Ahh, one of the dirty little secrets. If the base receives two 
> sequential outputs from a registered token, even if they are a long 
> way away from the currently expected output, it will resynchronize to 
> that.

I guess this varies. At least my former car had a warning in the manual,
regarding the remote, that it could get out of sync if I pressed the
buttons too many time while out of range. So I guess at least some
manufacturers did something a little bit better.

	/MaF

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