diff --git a/core/net/rpl/rpl-dag.c b/core/net/rpl/rpl-dag.c
index e103d65f9..08178d5ad 100644
--- a/core/net/rpl/rpl-dag.c
+++ b/core/net/rpl/rpl-dag.c
@@ -987,7 +987,7 @@ rpl_add_dag(uip_ipaddr_t *from, rpl_dio_t *dio)
      instance->dio_redundancy != dio->dag_redund ||
      instance->default_lifetime != dio->default_lifetime ||
      instance->lifetime_unit != dio->lifetime_unit) {
-    PRINTF("RPL: DIO for DAG instance %u uncompatible with previos DIO\n",
+    PRINTF("RPL: DIO for DAG instance %u incompatible with previous DIO\n",
 	   dio->instance_id);
     rpl_remove_parent(p);
     dag->used = 0;
@@ -1171,7 +1171,7 @@ rpl_process_dio(uip_ipaddr_t *from, rpl_dio_t *dio)
 	RPL_LOLLIPOP_INCREMENT(dag->version);
 	rpl_reset_dio_timer(instance);
       } else {
-        PRINTF("RPL: Global Repair\n");
+        PRINTF("RPL: Global repair\n");
         if(dio->prefix_info.length != 0) {
           if(dio->prefix_info.flags & UIP_ND6_RA_FLAG_AUTONOMOUS) {
             PRINTF("RPL : Prefix announced in DIO\n");
diff --git a/core/net/rpl/rpl-icmp6.c b/core/net/rpl/rpl-icmp6.c
index d1ff56837..a34eb06aa 100644
--- a/core/net/rpl/rpl-icmp6.c
+++ b/core/net/rpl/rpl-icmp6.c
@@ -176,12 +176,14 @@ dis_output(uip_ipaddr_t *addr)
   unsigned char *buffer;
   uip_ipaddr_t tmpaddr;
 
-  /* DAG Information Solicitation  - 2 bytes reserved      */
-  /*      0                   1                   2        */
-  /*      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3  */
-  /*     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
-  /*     |     Flags     |   Reserved    |   Option(s)...  */
-  /*     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
+  /*
+   * DAG Information Solicitation  - 2 bytes reserved
+   *      0                   1                   2
+   *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+   *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+   *     |     Flags     |   Reserved    |   Option(s)...
+   *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+   */
 
   buffer = UIP_ICMP_PAYLOAD;
   buffer[0] = buffer[1] = 0;
@@ -241,7 +243,7 @@ dio_input(void)
       PRINTLLADDR((uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER));
       PRINTF("\n");
     } else {
-      PRINTF("RPL: Out of Memory, dropping DIO from ");
+      PRINTF("RPL: Out of memory, dropping DIO from ");
       PRINT6ADDR(&from);
       PRINTF(", ");
       PRINTLLADDR((uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER));
@@ -383,7 +385,7 @@ dio_input(void)
       break;
     case RPL_OPTION_PREFIX_INFO:
       if(len != 32) {
-        PRINTF("RPL: DAG prefix info not ok, len != 32\n");
+        PRINTF("RPL: Invalid DAG prefix info, len != 32\n");
 	RPL_STAT(rpl_stats.malformed_msgs++);
         return;
       }
@@ -420,7 +422,7 @@ dio_output(rpl_instance_t *instance, uip_ipaddr_t *uc_addr)
 #endif /* !RPL_LEAF_ONLY */
 
 #if RPL_LEAF_ONLY
-  /* In leaf mode, we send DIO message only as unicasts in response to 
+  /* In leaf mode, we only send DIO messages as unicasts in response to 
      unicast DIS messages. */
   if(uc_addr == NULL) {
     PRINTF("RPL: LEAF ONLY have multicast addr: skip dio_output\n");
@@ -617,15 +619,13 @@ dao_input(void)
   sequence = buffer[pos++];
 
   dag = instance->current_dag;
-  /* Is the DAGID present? */
+  /* Is the DAG ID present? */
   if(flags & RPL_DAO_D_FLAG) {
     if(memcmp(&dag->dag_id, &buffer[pos], sizeof(dag->dag_id))) {
       PRINTF("RPL: Ignoring a DAO for a DAG different from ours\n");
       return;
     }
     pos += 16;
-  } else {
-    /* Perhaps, there are verification to do but ... */
   }
 
   learned_from = uip_is_addr_mcast(&dao_sender_addr) ?
diff --git a/core/net/rpl/rpl-mrhof.c b/core/net/rpl/rpl-mrhof.c
index 9d75f319b..634bec763 100644
--- a/core/net/rpl/rpl-mrhof.c
+++ b/core/net/rpl/rpl-mrhof.c
@@ -104,7 +104,7 @@ calculate_path_metric(rpl_parent_t *p)
 }
 
 static void
-reset(rpl_dag_t *sag)
+reset(rpl_dag_t *dag)
 {
   PRINTF("RPL: Reset MRHOF\n");
 }