Business WLAN | NW3166 & WDS encryption

Just looking for some clarification on this point.

I currently have 6 NWA3166 units setup to talk to each other using WDS, to eliminate the need
for physical cabling to each location.

I'm using WPA-PSK for the actual wireless network, but at the moment, I don't have encryption turned
on for the WDS links. (we turned it on, but it seems to affect the connections between the units, so it
was turned off again)

My question is this:

I understand that the connection between a wireless client (my laptop) and one of the WAP units is encrypted,
but what of the traffic between the WAPs? If I don't have WDS encryption turned on, is this sending information
in the clear? or is the original traffic still encrypted?

Thanks

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