Use an EPM (Ethernet Protection Module), a Junction Box with built-in surge suppression, and proper grounding.
Note that two of the three models of Junction Boxes have surge protection built in. The GS-3-SMCH and the GS-3-SMC2 have built-in suppression. The GS-3-SMC junction box doesn't.
SMC Junction Box
SMC has no built-in surge protection