I want to modify the objective function and use RSSI in place of ETX. I start by deleting all methods to calculate ETX in link-stats.c
Same thing for the new file rpl-rssi.c ( I use the same MRHOF file with modification) example what I modify
#include "net/routing/rpl-lite/rpl.h"
#include "net/nbr-table.h"
#include "net/link-stats.h"
/* Log configuration */
#include "sys/log.h"
#define LOG_MODULE "RPL"
#define LOG_LEVEL LOG_LEVEL_RPL
#ifdef RPL_RSSI_CONF_MAX_LINK_METRIC
#define MAX_LINK_METRIC RPL_RSSI_CONF_MAX_LINK_METRIC
#else /* RPL_RSSI_CONF_MAX_LINK_METRIC */
#define MAX_LINK_METRIC -100
#endif /* RPL_MRHOF_CONF_MAX_LINK_METRIC */
/* Reject parents that have a higher path cost than the following. */
#ifdef RPL_RSSI_CONF_MAX_PATH_COST
#define MAX_PATH_COST RPL_RSSI_CONF_MAX_PATH_COST
#else /* RPL_ISSR_CONF_MAX_PATH_COST */
#define MAX_PATH_COST -100
#endif /* RPL_RSSI_CONF_MAX_PATH_COST */
/* Additional, custom hysteresis based on time. If a neighbor was consistently
* better than our preferred parent for at least TIME_THRESHOLD, switch to
* this neighbor regardless of RANK_THRESHOLD. */
#define TIME_THRESHOLD (10 * 60 * CLOCK_SECOND)
/*---------------------------------------------------------------------------*/
static void
reset(void)
{
LOG_INFO("reset RSSIn");
}
/*---------------------------------------------------------------------------*/
static uint16_t
nbr_link_metric(rpl_nbr_t *nbr)
{
const struct link_stats *stats = rpl_neighbor_get_link_stats(nbr);
return stats != NULL ? stats->rssi : 0xffff;
}
/*---------------------------------------------------------------------------*/
static uint16_t
link_metric_to_rank(uint16_t rssi)
{
return rssi;
}
/*---------------------------------------------------------------------------*/
static uint16_t
nbr_path_cost(rpl_nbr_t *nbr)
{
uint16_t base;
if(nbr == NULL) {
return 0xffff;
}
#if RPL_WITH_MC
/* Handle the different MC types */
switch(curr_instance.mc.type) {
case RPL_DAG_MC_RSSI:
base = nbr->mc.obj.rssi;
break;
case RPL_DAG_MC_ENERGY:
base = nbr->mc.obj.energy.energy_est << 8;
break;
default:
base = nbr->rank;
break;
}
#else /* RPL_WITH_MC */
base = nbr->rank;
#endif /* RPL_WITH_MC */
/* path cost upper bound: 0xffff */
return MIN((uint32_t)base + link_metric_to_rank(nbr_link_metric(nbr)), 0xffff);
}
/*---------------------------------------------------------------------------*/
static rpl_rank_t
rank_via_nbr(rpl_nbr_t *nbr)
{
uint16_t min_hoprankinc;
uint16_t path_cost;
if(nbr == NULL) {
return RPL_INFINITE_RANK;
}
min_hoprankinc = curr_instance.min_hoprankinc;
path_cost = nbr_path_cost(nbr);
/* Rank lower-bound: nbr rank + min_hoprankinc */
return MAX(MIN((uint32_t)nbr->rank + min_hoprankinc, RPL_INFINITE_RANK), path_cost);
}
/*---------------------------------------------------------------------------*/
static int
nbr_has_usable_link(rpl_nbr_t *nbr)
{
uint16_t link_metric = nbr_link_metric(nbr);
/* Exclude links with too high link metrics */
return link_metric <= MAX_LINK_METRIC;
}
/*---------------------------------------------------------------------------*/
static int
nbr_is_acceptable_parent(rpl_nbr_t *nbr)
{
uint16_t path_cost = nbr_path_cost(nbr);
/* Exclude links with too high link metrics or path cost (RFC6719, 3.2.2) */
return nbr_has_usable_link(nbr) && path_cost <= MAX_PATH_COST;
}
/*---------------------------------------------------------------------------*/
static int
within_hysteresis(rpl_nbr_t *nbr)
{
uint16_t path_cost = nbr_path_cost(nbr);
uint16_t parent_path_cost = nbr_path_cost(curr_instance.dag.preferred_parent);
int within_rank_hysteresis = path_cost + RANK_THRESHOLD > parent_path_cost;
int within_time_hysteresis = nbr->better_parent_since == 0
|| (clock_time() - nbr->better_parent_since) <= TIME_THRESHOLD;
/* As we want to consider neighbors that are either beyond the rank or time
hystereses, return 1 here iff the neighbor is within both hystereses. */
return within_rank_hysteresis && within_time_hysteresis;
}
/*---------------------------------------------------------------------------*/
static rpl_nbr_t *
best_parent(rpl_nbr_t *nbr1, rpl_nbr_t *nbr2)
{
int nbr1_is_acceptable;
int nbr2_is_acceptable;
nbr1_is_acceptable = nbr1 != NULL && nbr_is_acceptable_parent(nbr1);
nbr2_is_acceptable = nbr2 != NULL && nbr_is_acceptable_parent(nbr2);
if(!nbr1_is_acceptable) {
return nbr2_is_acceptable ? nbr2 : NULL;
}
if(!nbr2_is_acceptable) {
return nbr1_is_acceptable ? nbr1 : NULL;
}
/* Maintain stability of the preferred parent. Switch only if the gain
is greater than RANK_THRESHOLD, or if the neighbor has been better than the
current parent for at more than TIME_THRESHOLD. */
if(nbr1 == curr_instance.dag.preferred_parent && within_hysteresis(nbr2)) {
return nbr1;
}
if(nbr2 == curr_instance.dag.preferred_parent && within_hysteresis(nbr1)) {
return nbr2;
}
return nbr_path_cost(nbr1) < nbr_path_cost(nbr2) ? nbr1 : nbr2;
}
/*---------------------------------------------------------------------------*/
#if !RPL_WITH_MC
static void
update_metric_container(void)
{
curr_instance.mc.type = RPL_DAG_MC_NONE;
}
#else /* RPL_WITH_MC */
static void
update_metric_container(void)
{
uint16_t path_cost;
uint8_t type;
if(!curr_instance.used) {
LOG_WARN("cannot update the metric container when not joinedn");
return;
}
if(curr_instance.dag.rank == ROOT_RANK) {
/* Configure MC at root only, other nodes are auto-configured when joining */
curr_instance.mc.type = RPL_DAG_MC;
curr_instance.mc.flags = 0;
curr_instance.mc.aggr = RPL_DAG_MC_AGGR_ADDITIVE;
curr_instance.mc.prec = 0;
path_cost = curr_instance.dag.rank;
} else {
path_cost = nbr_path_cost(curr_instance.dag.preferred_parent);
}
/* Handle the different MC types */
switch(curr_instance.mc.type) {
case RPL_DAG_MC_NONE:
break;
case RPL_DAG_MC_ETX:
curr_instance.mc.length = sizeof(curr_instance.mc.obj.etx);
curr_instance.mc.obj.etx = path_cost;
break;
case RPL_DAG_MC_ENERGY:
curr_instance.mc.length = sizeof(curr_instance.mc.obj.energy);
if(curr_instance.dag.rank == ROOT_RANK) {
type = RPL_DAG_MC_ENERGY_TYPE_MAINS;
} else {
type = RPL_DAG_MC_ENERGY_TYPE_BATTERY;
}
curr_instance.mc.obj.energy.flags = type << RPL_DAG_MC_ENERGY_TYPE;
/* Energy_est is only one byte, use the least significant byte of the path metric. */
curr_instance.mc.obj.energy.energy_est = path_cost >> 8;
break;
default:
LOG_WARN("MRHOF, non-supported MC %un", curr_instance.mc.type);
break;
}
}
#endif /* RPL_WITH_MC */
/*---------------------------------------------------------------------------*/
rpl_of_t rpl_rssi = {
reset,
nbr_link_metric,
nbr_has_usable_link,
nbr_is_acceptable_parent,
nbr_path_cost,
rank_via_nbr,
best_parent,
update_metric_container,
RPL_OCP_RSSI
};
In the end, when I run I notice that the root doesn’t receive any packet, and some motes who are far than the root show this msg dis_input: not in an instance yet, discard
Any help or hints I will be thinkfull