--- /dev/null
+#include <iomanip>
+
+#include "ethernet.h"
+
+std::ostream& operator<<(std::ostream& os, const ethernet_address& ea) {
+ auto& m = ea.mac;
+ using u = uint32_t;
+ os << std::hex << std::setw(2)
+ << u(m[0]) << ":"
+ << u(m[1]) << ":"
+ << u(m[2]) << ":"
+ << u(m[3]) << ":"
+ << u(m[4]) << ":"
+ << u(m[5]);
+ return os;
+}