- * Returns the number of contiguous bits belonging to the subnet, that have
- * to be masked out Example: A prefix network byte mask of ff.ff.ff.00 will
- * give a subnet mask length of 8, while ff.00.00.00 will return a subnet
- * mask length of 24. If the passed prefixMask object is null, 0 is returned
+ * Returns the prefix size in bits of the specified subnet mask. Example:
+ * For the subnet mask ff.ff.ff.e0 it returns 25 while for ff.00.00.00 it
+ * returns 8. If the passed subnetMask array is null, 0 is returned.