Hotspot + pppoe authentication & client isolation.

final+load+balancing.jpg
Here is my topology, copied from another forum, it works but there are some other problems. Please guide me .

  1. Can i use hotspot+ppoe authentication?
  2. Now Client1 can share files with client2 . How to do client isolation? Does my dlink unmanaged switch is ok(i guss not) or i need some advance switch/router with vlan capability.

Thanks in advance.

Confusion: how much pppoe connection can be done using lbl4 licence?
20 or 200?