|You would need to have minimally a 5 port switch in the location of the 4 pcs. The 5th port would have the wireless AP connected to it.|
You would need to create a wireless bridge between the AP and the router.
Depending on allowed hardware configs you can either have dhcp ip come from the router thru the AP to the pcs to from the AP to the pcs. Everything would need to be in the same subnet to talk.
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