Re network topology, following is abt all I know:
Typical SOHO network
Star Bus Topology
Motorola MB8611 DOCSIS 3.1 Cable Modem (2500 Mbps Max Internet Speed)
TP-Link AC1900 MU-MIMO WiFi Router (Archer A9)
Comcast Xfinity ISP cable 200Mbps
Belden 1700A Bonded Pair Cat 5e Ethernet Cables (longest 24')
4 Ethernet ports - (1) PC; (2) PC; (3) Tablo; (4) Fire TV
3 wireless connections (phones)
SPI (Stateful Packet Inspection) firewall enabled on router
Windows Defender Firewall on server PC.
No firewall (that I know of) on the Fire TV client.
Server and client configuration posted previously in this thread. Also posted internet speed.