[i]Hidden nodes are clients that can be seen by the AP and can see the AP but cannot see or be seen by one or more clients. [/i]
The hidden node problem is caused when a station cannot hear one of the other clients on the network
communicate. This results in packet collisions.
But I never knew a wireless station (like a Laptop) had to be aware of any other devices in the network. I thought the AP did this function. In the same way a drive relies on traffic light signals.
WLAN noobie btw
It creates a false clear channel assessment. When the laptop goes to transmit he checks to see if the air is clear. Because that node is hidden from him he may start talking when the other node is transmitting.
By definition, any client associated to an AP is within range of the AP - of course. By using the RTS/CTS or CTS-self on the AP, every client is notified of the up-coming transmission, and the effects of Hidden Node are mitigated.
And as I'm sure you've read, the amount of overhead increases, lowering throughput substantially. So pick your poison carefully.