diff --git a/src/include/netif/ppp/ppp.h b/src/include/netif/ppp/ppp.h
index ca4a4b81..9ffc8b4e 100644
--- a/src/include/netif/ppp/ppp.h
+++ b/src/include/netif/ppp/ppp.h
@@ -310,7 +310,6 @@ struct ppp_addrs {
  * PPP interface control block.
  */
 struct ppp_pcb_s {
-  /* -- below are data that will NOT be cleared between two sessions */
   ppp_settings settings;
   const struct link_callbacks *link_cb;
   void *link_ctx_cb;
@@ -320,13 +319,6 @@ struct ppp_pcb_s {
 #endif /* PPP_NOTIFY_PHASE */
   void *ctx_cb;                  /* Callbacks optional pointer */
   struct netif *netif;           /* PPP interface */
-
-  /* -- below are data that will be cleared between two sessions */
-
-  /*
-   * phase must be the first member of cleared members, because it is used to know
-   * which part must not be cleared.
-   */
   u8_t phase;                    /* where the link is at */
   u8_t err_code;                 /* Code indicating why interface is down. */
 
diff --git a/src/netif/ppp/ppp.c b/src/netif/ppp/ppp.c
index e9112111..16aba02f 100644
--- a/src/netif/ppp/ppp.c
+++ b/src/netif/ppp/ppp.c
@@ -697,11 +697,15 @@ void ppp_clear(ppp_pcb *pcb) {
 
   LWIP_ASSERT("pcb->phase == PPP_PHASE_DEAD || pcb->phase == PPP_PHASE_HOLDOFF", pcb->phase == PPP_PHASE_DEAD || pcb->phase == PPP_PHASE_HOLDOFF);
 
+  /* Clean data not taken care by anything else, mostly shared data. */
 #if PPP_STATS_SUPPORT
   link_stats_valid = 0;
 #endif /* PPP_STATS_SUPPORT */
-
-  memset(&pcb->phase, 0, sizeof(ppp_pcb) - ( (char*)&((ppp_pcb*)0)->phase - (char*)0 ) );
+#if MPPE_SUPPORT
+  pcb->mppe_keys_set = 0;
+  memset(&pcb->mppe_comp, 0, sizeof(pcb->mppe_comp));
+  memset(&pcb->mppe_decomp, 0, sizeof(pcb->mppe_decomp));
+#endif /* MPPE_SUPPORT */
 
   /*
    * Initialize each protocol.