int do_encap(int link, struct packet *new, const struct const_packet *old);
/*Connection functions*/
-int get_host(uint32_t src_id, uint32_t dest_id, int src_port, int dest_port, struct host *fwd, struct host *rev);
+int get_host(uint32_t src_id, uint32_t dest_id, int src_port, int dest_port, struct host **fwd, struct host **rev);
struct connection *add_connection(uint32_t src_id, uint32_t dest_id, int src_port, int dest_port);
int update_state(struct host* hst, enum con_state st);