Hmmm TCP/IP for 16 stations can be rather time consuming is that it ensure end-to-end reliability transfer due to routers in between 2 terminals. That's why it require a IP layer to allow routing through different network and TCP layer to ensure reliability and flow control. Kinda tiem consuming to implement these 2 layers assuming your physiacl + data link layer (HDLC) is done.
As for your case, since there's a master to regulate the flow, the contention will be minimal. Maybe you can take a look at a simple but not effective protocol, "Aloha".
However, let say your bandwidth is 1Mbps, it can only utilize up to a maximum of 18.4%. If you use Slotted Aloha, the effective bandwidth can be twice as much as pure aloha of 36.8%. However, slotted require synchronization.
Hope that helps !
Best Regards