+/* Convert 'speed' (measured in Mb/s) into the path cost. */
+uint16_t
+stp_convert_speed_to_cost(unsigned int speed)
+{
+ return speed >= 10000 ? 2 /* 10 Gb/s. */
+ : speed >= 1000 ? 4 /* 1 Gb/s. */
+ : speed >= 100 ? 19 /* 100 Mb/s. */
+ : speed >= 16 ? 62 /* 16 Mb/s. */
+ : speed >= 10 ? 100 /* 10 Mb/s. */
+ : speed >= 4 ? 250 /* 4 Mb/s. */
+ : 19; /* 100 Mb/s (guess). */
+}
+