The optical link is on the interface of the central router. The front panel of the main server is in the modern data center. High Speed SFP Module Stock Photo - Alamy
AC1100MSF Wireless AC VoIP Router with Fiber Port
UBIQUITI Gigabit Router with SFP, EdgeRouter™ 6P (ER-6P) - The source for WiFi products at best prices in Europe - wifi-stock.com
Intellinet 5-Port GbE PoE+ Switch w/ SFP Port (561822) – Intellinet Europe