Rsrteng Network Cable Tester, Remote Kits NO.1 to 5 or NO.6 to 10 for RJ45, Cat5,Cat6,5E,6E, Support Measure Length, Host/Test Box Fault Location, Short Circuit Test, Working with CCTV Camera Tester: Amazon.com: Industrial
Arduino Ethernet Cable Tester - Arduino Academy
Gadgetsmyth: Ethernet Switch Tester Using Raspberry PI - YouTube
Make Raspberry Pi Network SpeedTest Tool for Internal throughput and network speed measuring. - YouTube