+
+ router_valid = ntohs(adv->nd_ra_router_lifetime);
+
+ /* RFC4861 ยง6.3.7
+ * Once the host sends a Router Solicitation, and receives a valid
+ * Router Advertisement with a non-zero Router Lifetime, the host MUST
+ * desist from sending additional solicitations on that interface
+ * Moreover, a host SHOULD send at least one solicitation in the case
+ * where an advertisement is received prior to having sent a solicitation.
+ */
+ if (rs_attempt > 0 && router_valid > 0) {
+ alarm(0);
+ rs_attempt = 0;
+ }