Understanding Ethernet Link Detection and Energy Efficiency

This chapter of Heavy Networking explores how Ethernet adapters detect a loss of link signal, emphasizing that energy consumption is not reduced by transmitting less data as the carrier signal is always present. The conversation covers the history of Ethernet mechanisms like Marp and transitions to modern solutions like BFD for more efficient link monitoring. Additionally, the chapter touches on Power over Ethernet (PoE) intricacies, signaling protocols like OAM, and the importance of using direct current in PoE to avoid interference.