#define MIN(n) (n##u * 60u)
#define MEG(n) (n##ul * 1024ul * 1024ul)
+/* --- Timing parameters --- */
+
+#define T_EXP MIN(60) /* Expiry time for a key */
+#define T_REGEN MIN(40) /* Regeneration time for a key */
+
+#define T_VALID SEC(20) /* Challenge validity period */
+#define T_RETRY SEC(10) /* Challenge retransmit interval */
+
/* --- Other things --- */
#define PKBUFSZ 65536