diff --git a/src/netif/ppp/auth.c b/src/netif/ppp/auth.c
index 7e5d546b..694283e6 100644
--- a/src/netif/ppp/auth.c
+++ b/src/netif/ppp/auth.c
@@ -569,10 +569,11 @@ link_required(unit)
 void start_link(unit)
     int unit;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
     char *msg;
 
     status = EXIT_NEGOTIATION_FAILED;
-    new_phase(unit, PHASE_SERIALCONN);
+    new_phase(pcb, PHASE_SERIALCONN);
 
     hungup = 0;
     devfd = the_channel->connect();
@@ -608,18 +609,18 @@ void start_link(unit)
 	notice("Starting negotiation on %s", ppp_devnam);
     add_fd(fd_ppp);
 
-    new_phase(unit, PHASE_ESTABLISH);
+    new_phase(pcb, PHASE_ESTABLISH);
 
     lcp_lowerup(0);
     return;
 
  disconnect:
-    new_phase(unit, PHASE_DISCONNECT);
+    new_phase(pcb, PHASE_DISCONNECT);
     if (the_channel->disconnect)
 	the_channel->disconnect();
 
  fail:
-    new_phase(unit, PHASE_DEAD);
+    new_phase(pcb, PHASE_DEAD);
     if (the_channel->cleanup)
 	(*the_channel->cleanup)();
 }
@@ -633,10 +634,10 @@ void
 link_terminated(unit)
     int unit;
 {
-    ppp_pcb *pc = &ppp_pcb_list[unit];
-    if (pc->phase == PHASE_DEAD || pc->phase == PHASE_MASTER)
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
+    if (pcb->phase == PHASE_DEAD || pcb->phase == PHASE_MASTER)
 	return;
-    new_phase(unit, PHASE_DISCONNECT);
+    new_phase(pcb, PHASE_DISCONNECT);
 
 #if 0 /* UNUSED */
     if (pap_logout_hook) {
@@ -656,7 +657,7 @@ link_terminated(unit)
     lcp_lowerdown(0);
 
     new_phase(unit, PHASE_DEAD);
-    ppp_link_terminated(unit);
+    ppp_link_terminated(pcb);
 #if 0
     /*
      * Delete pid files before disestablishing ppp.  Otherwise it
@@ -697,11 +698,11 @@ link_terminated(unit)
 
     if (doing_multilink && multilink_master) {
 	if (!bundle_terminating)
-	    new_phase(unit, PHASE_MASTER);
+	    new_phase(pcb, PHASE_MASTER);
 	else
 	    mp_bundle_terminated();
     } else
-	new_phase(unit, PHASE_DEAD);
+	new_phase(pcb, PHASE_DEAD);
 #endif
 }
 
@@ -712,20 +713,20 @@ void
 link_down(unit)
     int unit;
 {
-    ppp_pcb *pc = &ppp_pcb_list[unit];
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
 #if PPP_NOTIFY
     notify(link_down_notifier, 0);
 #endif /* #if PPP_NOTIFY */
 
     if (!doing_multilink) {
 	upper_layers_down(unit);
-	if (pc->phase != PHASE_DEAD && pc->phase != PHASE_MASTER)
-	    new_phase(unit, PHASE_ESTABLISH);
+	if (pcb->phase != PHASE_DEAD && pcb->phase != PHASE_MASTER)
+	    new_phase(pcb, PHASE_ESTABLISH);
     }
     /* XXX if doing_multilink, should do something to stop
        network-layer traffic on the link */
 
-    ppp_link_down(unit);
+    ppp_link_down(pcb);
 }
 
 void upper_layers_down(int unit)
@@ -753,6 +754,7 @@ void
 link_established(unit)
     int unit;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
     int auth;
 #if 0 /* UNUSED */
     lcp_options *wo = &lcp_wantoptions[unit];
@@ -763,7 +765,6 @@ link_established(unit)
     lcp_options *ho = &lcp_hisoptions[unit];
     int i;
     struct protent *protp;
-    ppp_pcb *pc = &ppp_pcb_list[unit];
 
     /*
      * Tell higher-level protocols that LCP is up.
@@ -814,18 +815,18 @@ link_established(unit)
     }
 #endif /* UNUSED */
 
-    new_phase(unit, PHASE_AUTHENTICATE);
+    new_phase(pcb, PHASE_AUTHENTICATE);
     auth = 0;
 #if PPP_SERVER
 #if EAP_SUPPORT
     if (go->neg_eap) {
-	eap_authpeer(unit, pc->settings.our_name);
+	eap_authpeer(unit, pcb->settings.our_name);
 	auth |= EAP_PEER;
     } else
 #endif /* EAP_SUPPORT */
 #if CHAP_SUPPORT
     if (go->neg_chap) {
-	chap_auth_peer(unit, pc->settings.our_name, CHAP_DIGEST(go->chap_mdtype));
+	chap_auth_peer(unit, pcb->settings.our_name, CHAP_DIGEST(go->chap_mdtype));
 	auth |= CHAP_PEER;
     } else
 #endif /* CHAP_SUPPORT */
@@ -840,19 +841,19 @@ link_established(unit)
 
 #if EAP_SUPPORT
     if (ho->neg_eap) {
-	eap_authwithpeer(unit, pc->settings.user);
+	eap_authwithpeer(unit, pcb->settings.user);
 	auth |= EAP_WITHPEER;
     } else
 #endif /* EAP_SUPPORT */
 #if CHAP_SUPPORT
     if (ho->neg_chap) {
-	chap_auth_with_peer(unit, pc->settings.user, CHAP_DIGEST(ho->chap_mdtype));
+	chap_auth_with_peer(unit, pcb->settings.user, CHAP_DIGEST(ho->chap_mdtype));
 	auth |= CHAP_WITHPEER;
     } else
 #endif /* CHAP_SUPPORT */
 #if PAP_SUPPORT
     if (ho->neg_upap) {
-	upap_authwithpeer(unit, pc->settings.user, pc->settings.passwd);
+	upap_authwithpeer(unit, pcb->settings.user, pcb->settings.passwd);
 	auth |= PAP_WITHPEER;
     } else
 #endif /* PAP_SUPPORT */
@@ -872,6 +873,7 @@ static void
 network_phase(unit)
     int unit;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
 #if 0 /* UNUSED */
     lcp_options *go = &lcp_gotoptions[unit];
 #endif /* UNUSED */
@@ -906,7 +908,7 @@ network_phase(unit)
      * If we negotiated callback, do it now.
      */
     if (go->neg_cbcp) {
-	new_phase(unit, PHASE_CALLBACK);
+	new_phase(pcb, PHASE_CALLBACK);
 	(*cbcp_protent.open)(unit);
 	return;
     }
@@ -929,6 +931,7 @@ void
 start_networks(unit)
     int unit;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
 #if CCP_SUPPORT || ECP_SUPPORT
     int i;
     struct protent *protp;
@@ -940,7 +943,7 @@ start_networks(unit)
     int mppe_required;
 #endif /* MPPE */
 
-    new_phase(unit, PHASE_NETWORK);
+    new_phase(pcb, PHASE_NETWORK);
 
 #ifdef HAVE_MULTILINK
     if (multilink) {
@@ -1203,21 +1206,21 @@ np_up(unit, proto)
     int unit, proto;
 {
     int tlim;
-    ppp_pcb *pc = &ppp_pcb_list[unit];
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
 
     if (num_np_up == 0) {
 	/*
 	 * At this point we consider that the link has come up successfully.
 	 */
-	pc->status = EXIT_OK;
-	new_phase(unit, PHASE_RUNNING);
+	pcb->status = EXIT_OK;
+	new_phase(pcb, PHASE_RUNNING);
 
 #if 0 /* UNUSED */
 	if (idle_time_hook != 0)
 	    tlim = (*idle_time_hook)(NULL);
 	else
 #endif /* UNUSED */
-	    tlim = pc->settings.idle_time_limit;
+	    tlim = pcb->settings.idle_time_limit;
 	if (tlim > 0)
 	    TIMEOUT(check_idle, NULL, tlim);
 
@@ -1225,8 +1228,8 @@ np_up(unit, proto)
 	 * Set a timeout to close the connection once the maximum
 	 * connect time has expired.
 	 */
-	if (pc->settings.maxconnect > 0)
-	    TIMEOUT(connect_time_expired, 0, pc->settings.maxconnect);
+	if (pcb->settings.maxconnect > 0)
+	    TIMEOUT(connect_time_expired, 0, pcb->settings.maxconnect);
 
 #ifdef MAXOCTETS
 	if (maxoctets > 0)
@@ -1251,13 +1254,14 @@ void
 np_down(unit, proto)
     int unit, proto;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
     if (--num_np_up == 0) {
 	UNTIMEOUT(check_idle, NULL);
 	UNTIMEOUT(connect_time_expired, NULL);
 #ifdef MAXOCTETS
 	UNTIMEOUT(check_maxoctets, NULL);
 #endif
-	new_phase(unit, PHASE_NETWORK);
+	new_phase(pcb, PHASE_NETWORK);
     }
 }
 
@@ -1323,12 +1327,12 @@ check_idle(arg)
     void *arg;
 {
     /* FIXME: fix forced unit 0 */
-    ppp_pcb *pc = &ppp_pcb_list[0];
+    ppp_pcb *pcb = &ppp_pcb_list[0];
     struct ppp_idle idle;
     time_t itime;
     int tlim;
 
-    if (!get_idle_time(0, &idle))
+    if (!get_idle_time(pcb, &idle))
 	return;
 #if 0 /* UNUSED */
     if (idle_time_hook != 0) {
@@ -1336,14 +1340,14 @@ check_idle(arg)
     } else {
 #endif /* UNUSED */
 	itime = LWIP_MIN(idle.xmit_idle, idle.recv_idle);
-	tlim = pc->settings.idle_time_limit - itime;
+	tlim = pcb->settings.idle_time_limit - itime;
 #if 0 /* UNUSED */
     }
 #endif /* UNUSED */
     if (tlim <= 0) {
 	/* link is idle: shut it down. */
 	notice("Terminating connection due to lack of activity.");
-	pc->status = EXIT_IDLE_TIMEOUT;
+	pcb->status = EXIT_IDLE_TIMEOUT;
 	lcp_close(0, "Link inactive");
 #if 0 /* UNUSED */
 	need_holdoff = 0;
@@ -1361,9 +1365,9 @@ connect_time_expired(arg)
     void *arg;
 {
     /* FIXME: fix forced unit 0 */
-    ppp_pcb *pc = &ppp_pcb_list[0];
+    ppp_pcb *pcb = &ppp_pcb_list[0];
     info("Connect time expired");
-    pc->status = EXIT_CONNECT_TIME;
+    pcb->status = EXIT_CONNECT_TIME;
     lcp_close(0, "Connect time expired");	/* Close connection */
 }
 
@@ -1517,26 +1521,26 @@ auth_reset(unit)
 {
   lcp_options *go = &lcp_gotoptions[unit];
   lcp_options *ao = &lcp_allowoptions[unit];
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+  ppp_pcb *pcb = &ppp_pcb_list[unit];
 
-  if( pc->settings.passwd[0] ) {
+  if( pcb->settings.passwd[0] ) {
 
 #if PAP_SUPPORT
-    ao->neg_upap = !pc->settings.refuse_pap;
+    ao->neg_upap = !pcb->settings.refuse_pap;
 #endif /* PAP_SUPPORT */
 
 #if EAP_SUPPORT
-    ao->neg_eap = !pc->settings.refuse_eap;
+    ao->neg_eap = !pcb->settings.refuse_eap;
 #endif /* EAP_SUPPORT */
 
 #if CHAP_SUPPORT
     ao->chap_mdtype = MDTYPE_NONE;
-    if(!pc->settings.refuse_chap)
+    if(!pcb->settings.refuse_chap)
       ao->chap_mdtype |= MDTYPE_MD5;
 #if MSCHAP_SUPPORT
-    if(!pc->settings.refuse_mschap)
+    if(!pcb->settings.refuse_mschap)
       ao->chap_mdtype |= MDTYPE_MICROSOFT;
-    if(!pc->settings.refuse_mschap_v2)
+    if(!pcb->settings.refuse_mschap_v2)
       ao->chap_mdtype |= MDTYPE_MICROSOFT_V2;
 #endif /* MSCHAP_SUPPORT */
 
@@ -1990,23 +1994,23 @@ get_secret(unit, client, server, secret, secret_len, am_server)
     int am_server;
 {
   int len;
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+  ppp_pcb *pcb = &ppp_pcb_list[unit];
 
   LWIP_UNUSED_ARG(unit);
   LWIP_UNUSED_ARG(server);
   LWIP_UNUSED_ARG(am_server);
 
-  if(!client || !client[0] || strcmp(client, pc->settings.user)) {
+  if(!client || !client[0] || strcmp(client, pcb->settings.user)) {
     return 0;
   }
 
-  len = (int)strlen(pc->settings.passwd);
+  len = (int)strlen(pcb->settings.passwd);
   if (len > MAXSECRETLEN) {
     error("Secret for %s on %s is too long", client, server);
     len = MAXSECRETLEN;
   }
 
-  MEMCPY(secret, pc->settings.passwd, len);
+  MEMCPY(secret, pcb->settings.passwd, len);
   *secret_len = len;
 
   return 1;
diff --git a/src/netif/ppp/ccp.c b/src/netif/ppp/ccp.c
index d2e04569..de1ad4e8 100644
--- a/src/netif/ppp/ccp.c
+++ b/src/netif/ppp/ccp.c
@@ -1084,6 +1084,7 @@ ccp_reqci(f, p, lenp, dont_nak)
     int *lenp;
     int dont_nak;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     int ret, newret, res;
     u_char *p0, *retp;
     int len, clen, type, nb;
@@ -1200,9 +1201,9 @@ ccp_reqci(f, p, lenp, dont_nak)
 		     * because MPPE frames **grow**.  The kernel [must]
 		     * allocate MPPE_PAD extra bytes in xmit buffers.
 		     */
-		    mtu = netif_get_mtu(f->unit);
+		    mtu = netif_get_mtu(pcb);
 		    if (mtu)
-			netif_set_mtu(f->unit, mtu - MPPE_PAD);
+			netif_set_mtu(pcb, mtu - MPPE_PAD);
 		    else
 			newret = CONFREJ;
 		}
diff --git a/src/netif/ppp/chap-new.c b/src/netif/ppp/chap-new.c
index 62556c52..6d246dae 100644
--- a/src/netif/ppp/chap-new.c
+++ b/src/netif/ppp/chap-new.c
@@ -282,6 +282,8 @@ chap_auth_with_peer(int unit, char *our_name, int digest_code)
 static void
 chap_timeout(void *arg)
 {
+	/* FIXME: fix forced unit 0 */
+	ppp_pcb *pcb = &ppp_pcb_list[0];
 	struct chap_server_state *ss = arg;
 
 	ss->flags &= ~TIMEOUT_PENDING;
@@ -296,7 +298,7 @@ chap_timeout(void *arg)
 		return;
 	}
 
-	ppp_write(0, ss->challenge, ss->challenge_pktlen);
+	ppp_write(pcb, ss->challenge, ss->challenge_pktlen);
 	++ss->challenge_xmits;
 	ss->flags |= TIMEOUT_PENDING;
 	TIMEOUT(chap_timeout, arg, chap_timeout_time);
@@ -337,6 +339,8 @@ static void
 chap_handle_response(struct chap_server_state *ss, int id,
 		     unsigned char *pkt, int len)
 {
+	/* FIXME: fix forced unit 0 */
+	ppp_pcb *pcb = &ppp_pcb_list[0];
 	int response_len, ok, mlen;
 	unsigned char *response, *p;
 	char *name = NULL;	/* initialized to shut gcc up */
@@ -397,7 +401,7 @@ chap_handle_response(struct chap_server_state *ss, int id,
 	p[3] = len;
 	if (mlen > 0)
 		memcpy(p + CHAP_HDRLEN, ss->message, mlen);
-	ppp_write(0, outpacket_buf, PPP_HDRLEN + len);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + len);
 
 	if (ss->flags & CHALLENGE_VALID) {
 		ss->flags &= ~CHALLENGE_VALID;
@@ -474,6 +478,8 @@ static void
 chap_respond(struct chap_client_state *cs, int id,
 	     unsigned char *pkt, int len)
 {
+	/* FIXME: fix forced unit 0 */
+	ppp_pcb *pcb = &ppp_pcb_list[0];
 	int clen, nlen;
 	int secret_len;
 	unsigned char *p;
@@ -521,7 +527,7 @@ chap_respond(struct chap_client_state *cs, int id,
 	p[2] = len >> 8;
 	p[3] = len;
 
-	ppp_write(0, response, PPP_HDRLEN + len);
+	ppp_write(pcb, response, PPP_HDRLEN + len);
 }
 
 static void
diff --git a/src/netif/ppp/eap.c b/src/netif/ppp/eap.c
index 0e382313..95176380 100644
--- a/src/netif/ppp/eap.c
+++ b/src/netif/ppp/eap.c
@@ -268,6 +268,7 @@ static void
 eap_send_failure(esp)
 eap_state *esp;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 
 	outp = outpacket_buf;
@@ -279,7 +280,7 @@ eap_state *esp;
 	PUTCHAR(esp->es_server.ea_id, outp);
 	PUTSHORT(EAP_HEADERLEN, outp);
 
-	ppp_write(esp->es_unit, outpacket_buf, EAP_HEADERLEN + PPP_HDRLEN);
+	ppp_write(pcb, outpacket_buf, EAP_HEADERLEN + PPP_HDRLEN);
 
 	esp->es_server.ea_state = eapBadAuth;
 	auth_peer_fail(esp->es_unit, PPP_EAP);
@@ -293,6 +294,7 @@ static void
 eap_send_success(esp)
 eap_state *esp;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 
 	outp = outpacket_buf;
@@ -304,7 +306,7 @@ eap_state *esp;
 	PUTCHAR(esp->es_server.ea_id, outp);
 	PUTSHORT(EAP_HEADERLEN, outp);
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + EAP_HEADERLEN);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + EAP_HEADERLEN);
 
 	auth_peer_success(esp->es_unit, PPP_EAP, 0,
 	    esp->es_server.ea_peer, esp->es_server.ea_peerlen);
@@ -648,6 +650,7 @@ static void
 eap_send_request(esp)
 eap_state *esp;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	u_char *lenloc;
 	u_char *ptr;
@@ -867,7 +870,7 @@ eap_state *esp;
 	outlen = (outp - outpacket_buf) - PPP_HDRLEN;
 	PUTSHORT(outlen, lenloc);
 
-	ppp_write(esp->es_unit, outpacket_buf, outlen + PPP_HDRLEN);
+	ppp_write(pcb, outpacket_buf, outlen + PPP_HDRLEN);
 
 	esp->es_server.ea_requests++;
 
@@ -1066,6 +1069,7 @@ u_char typenum;
 u_char *str;
 int lenstr;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	int msglen;
 
@@ -1083,7 +1087,7 @@ int lenstr;
 		MEMCPY(outp, str, lenstr);
 	}
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + msglen);
 }
 
 /*
@@ -1097,6 +1101,7 @@ u_char *hash;
 char *name;
 int namelen;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	int msglen;
 
@@ -1118,7 +1123,7 @@ int namelen;
 		MEMCPY(outp, name, namelen);
 	}
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + msglen);
 }
 
 #ifdef USE_SRP
@@ -1133,6 +1138,7 @@ u_char subtypenum;
 u_char *str;
 int lenstr;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	int msglen;
 
@@ -1151,7 +1157,7 @@ int lenstr;
 		MEMCPY(outp, str, lenstr);
 	}
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + msglen);
 }
 
 /*
@@ -1164,6 +1170,7 @@ u_char id;
 u_int32_t flags;
 u_char *str;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	int msglen;
 
@@ -1182,7 +1189,7 @@ u_char *str;
 	PUTLONG(flags, outp);
 	MEMCPY(outp, str, SHA_DIGESTSIZE);
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + msglen);
 }
 #endif /* USE_SRP */
 
@@ -1192,6 +1199,7 @@ eap_state *esp;
 u_char id;
 u_char type;
 {
+	ppp_pcb *pcb = &ppp_pcb_list[esp->es_unit];
 	u_char *outp;
 	int msglen;
 
@@ -1207,7 +1215,7 @@ u_char type;
 	PUTCHAR(EAPT_NAK, outp);
 	PUTCHAR(type, outp);
 
-	ppp_write(esp->es_unit, outpacket_buf, PPP_HDRLEN + msglen);
+	ppp_write(pcb, outpacket_buf, PPP_HDRLEN + msglen);
 }
 
 #ifdef USE_SRP
diff --git a/src/netif/ppp/fsm.c b/src/netif/ppp/fsm.c
index 57b366b2..856ccfcd 100644
--- a/src/netif/ppp/fsm.c
+++ b/src/netif/ppp/fsm.c
@@ -808,6 +808,7 @@ fsm_sdata(f, code, id, data, datalen)
     u_char *data;
     int datalen;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     u_char *outp;
     int outlen;
 
@@ -822,7 +823,7 @@ fsm_sdata(f, code, id, data, datalen)
     PUTCHAR(code, outp);
     PUTCHAR(id, outp);
     PUTSHORT(outlen, outp);
-    ppp_write(f->unit, outpacket_buf, outlen + PPP_HDRLEN);
+    ppp_write(pcb, outpacket_buf, outlen + PPP_HDRLEN);
 }
 
 #endif /* PPP_SUPPORT */
diff --git a/src/netif/ppp/ipcp.c b/src/netif/ppp/ipcp.c
index 2434b5f1..3b8589e5 100644
--- a/src/netif/ppp/ipcp.c
+++ b/src/netif/ppp/ipcp.c
@@ -1756,6 +1756,7 @@ static int
 ip_demand_conf(u)
     int u;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[u];
     ipcp_options *wo = &ipcp_wantoptions[u];
 
     if (wo->hisaddr == 0 && !noremoteip) {
@@ -1769,18 +1770,18 @@ ip_demand_conf(u)
 	wo->accept_local = 1;
 	ask_for_local = 0;	/* don't tell the peer this address */
     }
-    if (!sifaddr(u, wo->ouraddr, wo->hisaddr, get_mask(wo->ouraddr)))
+    if (!sifaddr(pcb, wo->ouraddr, wo->hisaddr, get_mask(wo->ouraddr)))
 	return 0;
-    if (!sifup(u))
+    if (!sifup(pcb))
 	return 0;
-    if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE))
+    if (!sifnpmode(pcb, PPP_IP, NPMODE_QUEUE))
 	return 0;
     if (wo->default_route)
-	if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr,
+	if (sifdefaultroute(pcb, wo->ouraddr, wo->hisaddr,
 		wo->replace_default_route))
 	    default_route_set[u] = 1;
     if (wo->proxy_arp)
-	if (sifproxyarp(u, wo->hisaddr))
+	if (sifproxyarp(pcb, wo->hisaddr))
 	    proxy_arp_set[u] = 1;
 
     notice("local  IP address %I", wo->ouraddr);
@@ -1800,8 +1801,8 @@ static void
 ipcp_up(f)
     fsm *f;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     u_int32_t mask;
-    ppp_pcb *pc = &ppp_pcb_list[f->unit];
     ipcp_options *ho = &ipcp_hisoptions[f->unit];
     ipcp_options *go = &ipcp_gotoptions[f->unit];
     ipcp_options *wo = &ipcp_wantoptions[f->unit];
@@ -1846,8 +1847,8 @@ ipcp_up(f)
     if (go->dnsaddr[1])
 	script_setenv("DNS2", ip_ntoa(go->dnsaddr[1]), 0);
 #endif /* UNUSED */
-    if (pc->settings.usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) {
-	sdns(f->unit, go->dnsaddr[0], go->dnsaddr[1]);
+    if (pcb->settings.usepeerdns && (go->dnsaddr[0] || go->dnsaddr[1])) {
+	sdns(pcb, go->dnsaddr[0], go->dnsaddr[1]);
 #if 0 /* UNUSED */
 	script_setenv("USEPEERDNS", "1", 0);
 	create_resolv(go->dnsaddr[0], go->dnsaddr[1]);
@@ -1867,7 +1868,7 @@ ipcp_up(f)
 #endif /* Unused */
 
     /* set tcp compression */
-    sifvjcomp(f->unit, ho->neg_vj, ho->cflag, ho->maxslotindex);
+    sifvjcomp(pcb, ho->neg_vj, ho->cflag, ho->maxslotindex);
 
 #if DEMAND_SUPPORT
     /*
@@ -1894,7 +1895,7 @@ ipcp_up(f)
 
 	    /* Set the interface to the new addresses */
 	    mask = get_mask(go->ouraddr);
-	    if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
+	    if (!sifaddr(pcb, go->ouraddr, ho->hisaddr, mask)) {
 #if PPP_DEBUG
 		warn("Interface configuration failed");
 #endif /* PPP_DEBUG */
@@ -1904,18 +1905,18 @@ ipcp_up(f)
 
 	    /* assign a default route through the interface if required */
 	    if (ipcp_wantoptions[f->unit].default_route) 
-		if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr,
+		if (sifdefaultroute(pcb, go->ouraddr, ho->hisaddr,
 			wo->replace_default_route))
 		    default_route_set[f->unit] = 1;
 
 	    /* Make a proxy ARP entry if requested. */
 	    if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp)
-		if (sifproxyarp(f->unit, ho->hisaddr))
+		if (sifproxyarp(pcb, ho->hisaddr))
 		    proxy_arp_set[f->unit] = 1;
 
 	}
 	demand_rexmit(PPP_IP,go->ouraddr);
-	sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
+	sifnpmode(pcb, PPP_IP, NPMODE_PASS);
 
     } else
 #endif /* DEMAND_SUPPORT */
@@ -1926,7 +1927,7 @@ ipcp_up(f)
 	mask = get_mask(go->ouraddr);
 
 #if !(defined(SVR4) && (defined(SNI) || defined(__USLC__)))
-	if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
+	if (!sifaddr(pcb, go->ouraddr, ho->hisaddr, mask)) {
 #if PPP_DEBUG
 	    warn("Interface configuration failed");
 #endif /* PPP_DEBUG */
@@ -1936,7 +1937,7 @@ ipcp_up(f)
 #endif
 
 	/* bring the interface up for IP */
-	if (!sifup(f->unit)) {
+	if (!sifup(pcb)) {
 #if PPP_DEBUG
 	    warn("Interface failed to come up");
 #endif /* PPP_DEBUG */
@@ -1945,7 +1946,7 @@ ipcp_up(f)
 	}
 
 #if (defined(SVR4) && (defined(SNI) || defined(__USLC__)))
-	if (!sifaddr(f->unit, go->ouraddr, ho->hisaddr, mask)) {
+	if (!sifaddr(pcb, go->ouraddr, ho->hisaddr, mask)) {
 #if PPP_DEBUG
 	    warn("Interface configuration failed");
 #endif /* PPP_DEBUG */
@@ -1953,17 +1954,17 @@ ipcp_up(f)
 	    return;
 	}
 #endif
-	sifnpmode(f->unit, PPP_IP, NPMODE_PASS);
+	sifnpmode(pcb, PPP_IP, NPMODE_PASS);
 
 	/* assign a default route through the interface if required */
 	if (ipcp_wantoptions[f->unit].default_route) 
-	    if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr,
+	    if (sifdefaultroute(pcb, go->ouraddr, ho->hisaddr,
 		    wo->replace_default_route))
 		default_route_set[f->unit] = 1;
 
 	/* Make a proxy ARP entry if requested. */
 	if (ho->hisaddr != 0 && ipcp_wantoptions[f->unit].proxy_arp)
-	    if (sifproxyarp(f->unit, ho->hisaddr))
+	    if (sifproxyarp(pcb, ho->hisaddr))
 		proxy_arp_set[f->unit] = 1;
 
 	ipcp_wantoptions[0].ouraddr = go->ouraddr;
@@ -2004,6 +2005,7 @@ static void
 ipcp_down(f)
     fsm *f;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     IPCPDEBUG(("ipcp: down"));
 #if PPP_STATS_SUPPORT
     /* XXX a bit IPv4-centric here, we only need to get the stats
@@ -2023,7 +2025,7 @@ ipcp_down(f)
 	ipcp_is_up = 0;
 	np_down(f->unit, PPP_IP);
     }
-    sifvjcomp(f->unit, 0, 0, 0);
+    sifvjcomp(pcb, 0, 0, 0);
 
 #if PPP_STATS_SUPPORT
     print_link_stats(); /* _after_ running the notifiers and ip_down_hook(),
@@ -2037,15 +2039,15 @@ ipcp_down(f)
      * to queue up outgoing packets (for now).
      */
     if (demand) {
-	sifnpmode(f->unit, PPP_IP, NPMODE_QUEUE);
+	sifnpmode(pcb, PPP_IP, NPMODE_QUEUE);
     } else
 #endif /* DEMAND_SUPPORT */
     {
-	sifnpmode(f->unit, PPP_IP, NPMODE_DROP);
-	sifdown(f->unit);
+	sifnpmode(pcb, PPP_IP, NPMODE_DROP);
+	sifdown(pcb);
 	ipcp_clear_addrs(f->unit, ipcp_gotoptions[f->unit].ouraddr,
 			 ipcp_hisoptions[f->unit].hisaddr, 0);
-	cdns(f->unit, ipcp_gotoptions[f->unit].dnsaddr[0], ipcp_gotoptions[f->unit].dnsaddr[1]);
+	cdns(pcb, ipcp_gotoptions[f->unit].dnsaddr[0], ipcp_gotoptions[f->unit].dnsaddr[1]);
     }
 }
 
@@ -2056,8 +2058,10 @@ ipcp_down(f)
  */
 static void ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, bool replacedefaultroute) {
 
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
+
     if (proxy_arp_set[unit]) {
-	cifproxyarp(unit, hisaddr);
+	cifproxyarp(pcb, hisaddr);
 	proxy_arp_set[unit] = 0;
     }
     /* If replacedefaultroute, sifdefaultroute will be called soon
@@ -2069,10 +2073,10 @@ static void ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, boo
      * is one saved by an sifdefaultroute with replacedefaultroute.
      */
     if (!replacedefaultroute && default_route_set[unit]) {
-	cifdefaultroute(unit, ouraddr, hisaddr);
+	cifdefaultroute(pcb, ouraddr, hisaddr);
 	default_route_set[unit] = 0;
     }
-    cifaddr(unit, ouraddr, hisaddr);
+    cifaddr(pcb, ouraddr, hisaddr);
 }
 
 
diff --git a/src/netif/ppp/lcp.c b/src/netif/ppp/lcp.c
index 12fbe0de..acfd4116 100644
--- a/src/netif/ppp/lcp.c
+++ b/src/netif/ppp/lcp.c
@@ -462,12 +462,12 @@ lcp_close(unit, reason)
     int unit;
     char *reason;
 {
-    ppp_pcb *pc = &ppp_pcb_list[unit];
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
     fsm *f = &lcp_fsm[unit];
     int oldstate;
 
-    if (pc->phase != PHASE_DEAD && pc->phase != PHASE_MASTER)
-	new_phase(unit, PHASE_TERMINATE);
+    if (pcb->phase != PHASE_DEAD && pcb->phase != PHASE_MASTER)
+	new_phase(pcb, PHASE_TERMINATE);
 
     if (f->flags & DELAYED_UP) {
 	UNTIMEOUT(lcp_delayed_up, f);
@@ -497,19 +497,19 @@ void
 lcp_lowerup(unit)
     int unit;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[unit];
     lcp_options *wo = &lcp_wantoptions[unit];
     fsm *f = &lcp_fsm[unit];
-    ppp_pcb *pc = &ppp_pcb_list[unit];
     /*
      * Don't use A/C or protocol compression on transmission,
      * but accept A/C and protocol compressed packets
      * if we are going to ask for A/C and protocol compression.
      */
 #if PPPOS_SUPPORT
-    ppp_set_xaccm(unit, &xmit_accm[unit]);
+    ppp_set_xaccm(pcb, &xmit_accm[unit]);
 #endif /* PPPOS_SUPPORT */
-    if (ppp_send_config(unit, PPP_MRU, 0xffffffff, 0, 0) < 0
-	|| ppp_recv_config(unit, PPP_MRU, (lax_recv? 0: 0xffffffff),
+    if (ppp_send_config(pcb, PPP_MRU, 0xffffffff, 0, 0) < 0
+	|| ppp_recv_config(pcb, PPP_MRU, (lax_recv? 0: 0xffffffff),
 			   wo->neg_pcompression, wo->neg_accompression) < 0)
 	    return;
     peer_mru[unit] = PPP_MRU;
@@ -526,9 +526,9 @@ lcp_lowerup(unit)
               xmit_accm[unit][0]));
 #endif /* PPPOS_SUPPORT */
 
-    if (pc->settings.listen_time != 0) {
+    if (pcb->settings.listen_time != 0) {
 	f->flags |= DELAYED_UP;
-	TIMEOUTMS(lcp_delayed_up, f, pc->settings.listen_time);
+	TIMEOUTMS(lcp_delayed_up, f, pcb->settings.listen_time);
     } else
 	fsm_lowerup(f);
 }
@@ -2278,6 +2278,7 @@ static void
 lcp_up(f)
     fsm *f;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     lcp_options *wo = &lcp_wantoptions[f->unit];
     lcp_options *ho = &lcp_hisoptions[f->unit];
     lcp_options *go = &lcp_gotoptions[f->unit];
@@ -2303,11 +2304,11 @@ lcp_up(f)
 #ifdef HAVE_MULTILINK
     if (!(multilink && go->neg_mrru && ho->neg_mrru))
 #endif /* HAVE_MULTILINK */
-	netif_set_mtu(f->unit, LWIP_MIN(LWIP_MIN(mtu, mru), ao->mru));
-    ppp_send_config(f->unit, mtu,
+	netif_set_mtu(pcb, LWIP_MIN(LWIP_MIN(mtu, mru), ao->mru));
+    ppp_send_config(pcb, mtu,
 		    (ho->neg_asyncmap? ho->asyncmap: 0xffffffff),
 		    ho->neg_pcompression, ho->neg_accompression);
-    ppp_recv_config(f->unit, mru,
+    ppp_recv_config(pcb, mru,
 		    (lax_recv? 0: go->neg_asyncmap? go->asyncmap: 0xffffffff),
 		    go->neg_pcompression, go->neg_accompression);
 
@@ -2329,14 +2330,15 @@ static void
 lcp_down(f)
     fsm *f;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[f->unit];
     lcp_options *go = &lcp_gotoptions[f->unit];
 
     lcp_echo_lowerdown(f->unit);
 
     link_down(f->unit);
 
-    ppp_send_config(f->unit, PPP_MRU, 0xffffffff, 0, 0);
-    ppp_recv_config(f->unit, PPP_MRU,
+    ppp_send_config(pcb, PPP_MRU, 0xffffffff, 0, 0);
+    ppp_recv_config(pcb, PPP_MRU,
 		    (go->neg_asyncmap? go->asyncmap: 0xffffffff),
 		    go->neg_pcompression, go->neg_accompression);
     peer_mru[f->unit] = PPP_MRU;
diff --git a/src/netif/ppp/ppp.c b/src/netif/ppp/ppp.c
index d5012819..e4851095 100644
--- a/src/netif/ppp/ppp.c
+++ b/src/netif/ppp/ppp.c
@@ -126,25 +126,6 @@
 /*** LOCAL DEFINITIONS ***/
 /*************************/
 
-/** PPP_INPROC_MULTITHREADED==1 call ppp_input using tcpip_callback().
- * Set this to 0 if pppos_input_proc is called inside tcpip_thread or with NO_SYS==1.
- * Default is 1 for NO_SYS==0 (multithreaded) and 0 for NO_SYS==1 (single-threaded).
- */
-#ifndef PPP_INPROC_MULTITHREADED
-#define PPP_INPROC_MULTITHREADED (NO_SYS==0)
-#endif
-
-/** PPP_INPROC_OWNTHREAD==1: start a dedicated RX thread per PPP session.
- * Default is 0: call pppos_input() for received raw characters, character
- * reception is up to the port */
-#ifndef PPP_INPROC_OWNTHREAD
-#define PPP_INPROC_OWNTHREAD      PPP_INPROC_MULTITHREADED
-#endif
-
-#if PPP_INPROC_OWNTHREAD && !PPP_INPROC_MULTITHREADED
-  #error "PPP_INPROC_OWNTHREAD needs PPP_INPROC_MULTITHREADED==1"
-#endif
-
 /*
  * Buffers for outgoing packets.  This must be accessed only from the appropriate
  * PPP task so that it doesn't need to be protected to avoid collisions.
@@ -201,24 +182,7 @@ struct protent *protocols[] = {
 };
 
 #if PPPOS_SUPPORT
-/* PPP packet parser states.  Current state indicates operation yet to be
- * completed. */
-typedef enum {
-  PDIDLE = 0,  /* Idle state - waiting. */
-  PDSTART,     /* Process start flag. */
-  PDADDRESS,   /* Process address field. */
-  PDCONTROL,   /* Process control field. */
-  PDPROTOCOL1, /* Process protocol field 1. */
-  PDPROTOCOL2, /* Process protocol field 2. */
-  PDDATA       /* Process data byte. */
-} ppp_dev_states;
-
 #define ESCAPE_P(accm, c) ((accm)[(c) >> 3] & ppp_accm_mask[c & 0x07])
-
-/** RX buffer size: this may be configured smaller! */
-#ifndef PPPOS_RX_BUFSIZE
-#define PPPOS_RX_BUFSIZE    (PPP_MRU + PPP_HDRLEN)
-#endif
 #endif /* PPPOS_SUPPORT */
 
 /* Prototypes for procedures local to this file. */
@@ -227,7 +191,7 @@ static void ppp_start(int pd);		/** Initiate LCP open request */
 static void ppp_input(int unit, void *arg);
 
 #if PPPOS_SUPPORT
-static void ppp_receive_wakeup(int pd);
+static void ppp_receive_wakeup(ppp_pcb *pcb);
 #endif /* #if PPPOS_SUPPORT */
 
 static void ppp_stop(int pd);
@@ -246,9 +210,9 @@ static err_t ppp_netif_init_cb(struct netif *netif);
 static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *ipaddr);
 
 #if PPPOE_SUPPORT
-static err_t ppp_netif_output_over_ethernet(int pd, struct pbuf *p);
+static err_t ppp_netif_output_over_ethernet(ppp_pcb *pcb, struct pbuf *p);
 /* function called by ppp_write() */
-static int ppp_write_over_ethernet(int pd, const u_char *s, int n);
+static int ppp_write_over_ethernet(ppp_pcb *pcb, const u_char *s, int n);
 #endif /* PPPOE_SUPPORT */
 
 /******************************/
@@ -308,7 +272,7 @@ ppp_pcb *ppp_new(void) {
     pcb->unit = pd;
     pcb->open_flag = 1;
     pcb->status = EXIT_OK;
-    new_phase(pd, PHASE_INITIALIZE);
+    new_phase(pcb, PHASE_INITIALIZE);
 
     pcb->settings.usepeerdns = 1;
     pcb->settings.persist = 1;
@@ -390,7 +354,7 @@ int ppp_over_serial_open(ppp_pcb *pcb, sio_fd_t fd, ppp_link_status_cb_fn link_s
 
   pcb->fd = fd;
 
-  pcb->rx.pd = unit;
+  pcb->rx.pd = pcb->unit;
   pcb->rx.fd = fd;
 
 #if VJ_SUPPORT
@@ -410,26 +374,26 @@ int ppp_over_serial_open(ppp_pcb *pcb, sio_fd_t fd, ppp_link_status_cb_fn link_s
   /*
    * Start the connection and handle incoming events (packet or timeout).
    */
-  PPPDEBUG(LOG_INFO, ("ppp_over_serial_open: unit %d: Connecting\n", pd));
-  ppp_start(unit);
+  PPPDEBUG(LOG_INFO, ("ppp_over_serial_open: unit %d: Connecting\n", pcb->unit));
+  ppp_start(pcb->unit);
 #if PPP_INPROC_OWNTHREAD
   sys_thread_new(PPP_THREAD_NAME, ppp_input_thread, (void*)&pcb->rx, PPP_THREAD_STACKSIZE, PPP_THREAD_PRIO);
 #endif /* PPP_INPROC_OWNTHREAD */
 
-  return unit;
+  return pcb->unit;
 }
 
 /*
  * ppp_set_xaccm - set the extended transmit ACCM for the interface.
  */
-void ppp_set_xaccm(int unit, ext_accm *accm) {
-  SMEMCPY(ppp_pcb_list[unit].out_accm, accm, sizeof(ext_accm));
+void ppp_set_xaccm(ppp_pcb *pcb, ext_accm *accm) {
+  SMEMCPY(pcb->out_accm, accm, sizeof(ext_accm));
   PPPDEBUG(LOG_INFO, ("ppp_set_xaccm[%d]: out_accm=%X %X %X %X\n",
-            unit,
-            ppp_pcb_list[unit].out_accm[0],
-            ppp_pcb_list[unit].out_accm[1],
-            ppp_pcb_list[unit].out_accm[2],
-            ppp_pcb_list[unit].out_accm[3]));
+            pcb->unit,
+            pcb->out_accm[0],
+            pcb->out_accm[1],
+            pcb->out_accm[2],
+            pcb->out_accm[3]));
 }
 #endif /* PPPOS_SUPPORT */
 
@@ -500,7 +464,7 @@ ppp_close(ppp_pcb *pcb)
     /* This will leave us at PHASE_DEAD. */
     ppp_stop(pcb->unit);
 #if PPP_INPROC_OWNTHREAD
-    ppp_receive_wakeup(pcb->unit);
+    ppp_receive_wakeup(pcb);
 #endif /* PPP_INPROC_OWNTHREAD */
 #endif /* PPPOS_SUPPORT */
   }
@@ -554,7 +518,7 @@ ppp_hup(int pd)
  * or it is used in output ?  have to find out...
  */
 static void ppp_input(int unit, void *arg) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+  ppp_pcb *pcb = &ppp_pcb_list[unit];
   struct pbuf *nb = (struct pbuf *)arg;
   u16_t protocol;
   int pd;
@@ -583,7 +547,7 @@ static void ppp_input(int unit, void *arg) {
    * Until we get past the authentication phase, toss all packets
    * except LCP, LQR and authentication packets.
    */
-  if (pc->phase <= PHASE_AUTHENTICATE
+  if (pcb->phase <= PHASE_AUTHENTICATE
 	&& !(protocol == PPP_LCP
 #if LQR_SUPPORT
 	     || protocol == PPP_LQR
@@ -599,7 +563,7 @@ static void ppp_input(int unit, void *arg) {
 #endif /* EAP_SUPPORT */
 	     )) {
 	dbglog("discarding proto 0x%x in phase %d",
-		   protocol, pc->phase);
+		   protocol, pcb->phase);
 	goto drop;
   }
 
@@ -856,12 +820,11 @@ static u_char ppp_accm_mask[] = {
 #if PPP_INPROC_OWNTHREAD
 /** Wake up the task blocked in reading from serial line (if any) */
 static void
-ppp_receive_wakeup(int pd)
+ppp_receive_wakeup(ppp_pcb *pcb)
 {
-  PPPDEBUG(LOG_DEBUG, ("ppp_receive_wakeup: unit %d\n", pd));
-  if (ppp_pcb_list[pd].open_flag != 0) {
-    sio_read_abort(ppp_pcb_list[pd].fd);
-  }
+  PPPDEBUG(LOG_DEBUG, ("ppp_receive_wakeup: unit %d\n", pcb->unit));
+  if (pcb->open_flag != 0)
+    sio_read_abort(pcb->fd);
 }
 #endif /* PPP_INPROC_OWNTHREAD */
 #endif /* PPPOS_SUPPORT */
@@ -921,7 +884,7 @@ static err_t ppp_netif_init_cb(struct netif *netif) {
   netif->name[0] = 'p';
   netif->name[1] = 'p';
   netif->output = ppp_netif_output;
-  netif->mtu = netif_get_mtu((int)(size_t)netif->state);
+  netif->mtu = netif_get_mtu((ppp_pcb*)netif->state);
   netif->flags = NETIF_FLAG_POINTTOPOINT | NETIF_FLAG_LINK_UP;
 #if LWIP_NETIF_HOSTNAME
   /* @todo: Initialize interface hostname */
@@ -943,8 +906,9 @@ ppp_input_thread(void *arg)
 {
   int count;
   ppp_pcb_rx *pcrx = arg;
+  ppp_pcb *pcb = &ppp_pcb_list[pcrx->pd];
 
-  while (phase != PHASE_DEAD) {
+  while (pcb->phase != PHASE_DEAD) {
     count = sio_read(pcrx->fd, pcrx->rxbuf, PPPOS_RX_BUFSIZE);
     if(count > 0) {
       pppos_input_proc(pcrx, pcrx->rxbuf, count);
@@ -959,25 +923,25 @@ ppp_input_thread(void *arg)
 
 #if PPPOS_SUPPORT
 static void
-pppos_put(ppp_pcb *pc, struct pbuf *nb)
+pppos_put(ppp_pcb *pcb, struct pbuf *nb)
 {
   struct pbuf *b;
   int c;
 
   for(b = nb; b != NULL; b = b->next) {
-    if((c = sio_write(pc->fd, b->payload, b->len)) != b->len) {
+    if((c = sio_write(pcb->fd, b->payload, b->len)) != b->len) {
       PPPDEBUG(LOG_WARNING,
-               ("PPP pppos_put: incomplete sio_write(fd:%"SZT_F", len:%d, c: 0x%"X8_F") c = %d\n", (size_t)pc->fd, b->len, c, c));
+               ("PPP pppos_put: incomplete sio_write(fd:%"SZT_F", len:%d, c: 0x%"X8_F") c = %d\n", (size_t)pcb->fd, b->len, c, c));
       LINK_STATS_INC(link.err);
-      pc->last_xmit = 0; /* prepend PPP_FLAG to next packet */
-      snmp_inc_ifoutdiscards(&pc->netif);
+      pcb->last_xmit = 0; /* prepend PPP_FLAG to next packet */
+      snmp_inc_ifoutdiscards(&pcb->netif);
       pbuf_free(nb);
       return;
     }
   }
 
-  snmp_add_ifoutoctets(&pc->netif, nb->tot_len);
-  snmp_inc_ifoutucastpkts(&pc->netif);
+  snmp_add_ifoutoctets(&pcb->netif, nb->tot_len);
+  snmp_inc_ifoutucastpkts(&pcb->netif);
   pbuf_free(nb);
   LINK_STATS_INC(link.xmit);
 }
@@ -1025,8 +989,7 @@ ppp_append(u_char c, struct pbuf *nb, ext_accm *out_accm)
  * This is the low level function that send the PPP packet.
  */
 static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *ipaddr) {
-  int pd = (int)(size_t)netif->state;
-  ppp_pcb *pc = &ppp_pcb_list[pd];
+  ppp_pcb *pcb = (ppp_pcb*)netif->state;
 #if PPPOS_SUPPORT
   u_short protocol = PPP_IP;
   u_int fcs_out = PPP_INITFCS;
@@ -1039,9 +1002,9 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   /* Validate parameters. */
   /* We let any protocol value go through - it can't hurt us
    * and the peer will just drop it if it's not accepting it. */
-  if (pd < 0 || pd >= NUM_PPP || !pc->open_flag || !pb) {
+  if (!pcb->open_flag || !pb) {
     PPPDEBUG(LOG_WARNING, ("ppp_netif_output[%d]: bad params prot=%d pb=%p\n",
-              pd, PPP_IP, (void*)pb));
+              pcb->unit, PPP_IP, (void*)pb));
     LINK_STATS_INC(link.opterr);
     LINK_STATS_INC(link.drop);
     snmp_inc_ifoutdiscards(netif);
@@ -1049,8 +1012,8 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   }
 
   /* Check that the link is up. */
-  if (pc->phase == PHASE_DEAD) {
-    PPPDEBUG(LOG_ERR, ("ppp_netif_output[%d]: link not up\n", pd));
+  if (pcb->phase == PHASE_DEAD) {
+    PPPDEBUG(LOG_ERR, ("ppp_netif_output[%d]: link not up\n", pcb->unit));
     LINK_STATS_INC(link.rterr);
     LINK_STATS_INC(link.drop);
     snmp_inc_ifoutdiscards(netif);
@@ -1058,8 +1021,8 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   }
 
 #if PPPOE_SUPPORT
-  if(pc->ethif) {
-    return ppp_netif_output_over_ethernet(pd, pb);
+  if(pcb->ethif) {
+    return ppp_netif_output_over_ethernet(pcb, pb);
   }
 #endif /* PPPOE_SUPPORT */
 
@@ -1067,7 +1030,7 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   /* Grab an output buffer. */
   head = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
   if (head == NULL) {
-    PPPDEBUG(LOG_WARNING, ("ppp_netif_output[%d]: first alloc fail\n", pd));
+    PPPDEBUG(LOG_WARNING, ("ppp_netif_output[%d]: first alloc fail\n", pcb->unit));
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.drop);
     snmp_inc_ifoutdiscards(netif);
@@ -1079,8 +1042,8 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
    * Attempt Van Jacobson header compression if VJ is configured and
    * this is an IP packet.
    */
-  if (protocol == PPP_IP && pc->vj_enabled) {
-    switch (vj_compress_tcp(&pc->vj_comp, pb)) {
+  if (protocol == PPP_IP && pcb->vj_enabled) {
+    switch (vj_compress_tcp(&pcb->vj_comp, pb)) {
       case TYPE_IP:
         /* No change...
            protocol = PPP_IP_PROTOCOL; */
@@ -1092,7 +1055,7 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
         protocol = PPP_VJC_UNCOMP;
         break;
       default:
-        PPPDEBUG(LOG_WARNING, ("ppp_netif_output[%d]: bad IP packet\n", pd));
+        PPPDEBUG(LOG_WARNING, ("ppp_netif_output[%d]: bad IP packet\n", pcb->unit));
         LINK_STATS_INC(link.proterr);
         LINK_STATS_INC(link.drop);
         snmp_inc_ifoutdiscards(netif);
@@ -1105,25 +1068,25 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   tail = head;
 
   /* Build the PPP header. */
-  if ((sys_jiffies() - pc->last_xmit) >= PPP_MAXIDLEFLAG) {
+  if ((sys_jiffies() - pcb->last_xmit) >= PPP_MAXIDLEFLAG) {
     tail = ppp_append(PPP_FLAG, tail, NULL);
   }
 
-  pc->last_xmit = sys_jiffies();
-  if (!pc->accomp) {
+  pcb->last_xmit = sys_jiffies();
+  if (!pcb->accomp) {
     fcs_out = PPP_FCS(fcs_out, PPP_ALLSTATIONS);
-    tail = ppp_append(PPP_ALLSTATIONS, tail, &pc->out_accm);
+    tail = ppp_append(PPP_ALLSTATIONS, tail, &pcb->out_accm);
     fcs_out = PPP_FCS(fcs_out, PPP_UI);
-    tail = ppp_append(PPP_UI, tail, &pc->out_accm);
+    tail = ppp_append(PPP_UI, tail, &pcb->out_accm);
   }
-  if (!pc->pcomp || protocol > 0xFF) {
+  if (!pcb->pcomp || protocol > 0xFF) {
     c = (protocol >> 8) & 0xFF;
     fcs_out = PPP_FCS(fcs_out, c);
-    tail = ppp_append(c, tail, &pc->out_accm);
+    tail = ppp_append(c, tail, &pcb->out_accm);
   }
   c = protocol & 0xFF;
   fcs_out = PPP_FCS(fcs_out, c);
-  tail = ppp_append(c, tail, &pc->out_accm);
+  tail = ppp_append(c, tail, &pcb->out_accm);
 
   /* Load packet. */
   for(p = pb; p; p = p->next) {
@@ -1139,22 +1102,22 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
       fcs_out = PPP_FCS(fcs_out, c);
 
       /* Copy to output buffer escaping special characters. */
-      tail = ppp_append(c, tail, &pc->out_accm);
+      tail = ppp_append(c, tail, &pcb->out_accm);
     }
   }
 
   /* Add FCS and trailing flag. */
   c = ~fcs_out & 0xFF;
-  tail = ppp_append(c, tail, &pc->out_accm);
+  tail = ppp_append(c, tail, &pcb->out_accm);
   c = (~fcs_out >> 8) & 0xFF;
-  tail = ppp_append(c, tail, &pc->out_accm);
+  tail = ppp_append(c, tail, &pcb->out_accm);
   tail = ppp_append(PPP_FLAG, tail, NULL);
 
   /* If we failed to complete the packet, throw it away. */
   if (!tail) {
     PPPDEBUG(LOG_WARNING,
              ("ppp_netif_output[%d]: Alloc err - dropping proto=%d\n",
-              pd, protocol));
+              pcb->unit, protocol));
     pbuf_free(head);
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.drop);
@@ -1163,17 +1126,16 @@ static err_t ppp_netif_output(struct netif *netif, struct pbuf *pb, ip_addr_t *i
   }
 
   /* Send it. */
-  PPPDEBUG(LOG_INFO, ("ppp_netif_output[%d]: proto=0x%"X16_F"\n", pd, protocol));
+  PPPDEBUG(LOG_INFO, ("ppp_netif_output[%d]: proto=0x%"X16_F"\n", pcb->unit, protocol));
 
-  pppos_put(pc, head);
+  pppos_put(pcb, head);
 #endif /* PPPOS_SUPPORT */
 
   return ERR_OK;
 }
 
 #if PPPOE_SUPPORT
-static err_t ppp_netif_output_over_ethernet(int pd, struct pbuf *p) {
-  ppp_pcb *pc = &ppp_pcb_list[pd];
+static err_t ppp_netif_output_over_ethernet(ppp_pcb *pcb, struct pbuf *p) {
   struct pbuf *pb;
   u_short protocol = PPP_IP;
   int i=0;
@@ -1184,15 +1146,15 @@ static err_t ppp_netif_output_over_ethernet(int pd, struct pbuf *p) {
   if(!pb) {
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.proterr);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return ERR_MEM;
   }
 
   pbuf_header(pb, -(s16_t)PPPOE_HDRLEN);
 
-  pc->last_xmit = sys_jiffies();
+  pcb->last_xmit = sys_jiffies();
 
-  if (!pc->pcomp || protocol > 0xFF) {
+  if (!pcb->pcomp || protocol > 0xFF) {
     *((u_char*)pb->payload + i++) = (protocol >> 8) & 0xFF;
   }
   *((u_char*)pb->payload + i) = protocol & 0xFF;
@@ -1200,14 +1162,14 @@ static err_t ppp_netif_output_over_ethernet(int pd, struct pbuf *p) {
   pbuf_chain(pb, p);
   tot_len = pb->tot_len;
 
-  if(pppoe_xmit(pc->pppoe_sc, pb) != ERR_OK) {
+  if(pppoe_xmit(pcb->pppoe_sc, pb) != ERR_OK) {
     LINK_STATS_INC(link.err);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return PPPERR_DEVICE;
   }
 
-  snmp_add_ifoutoctets(&pc->netif, tot_len);
-  snmp_inc_ifoutucastpkts(&pc->netif);
+  snmp_add_ifoutoctets(&pcb->netif, tot_len);
+  snmp_inc_ifoutucastpkts(&pcb->netif);
   LINK_STATS_INC(link.xmit);
   return ERR_OK;
 }
@@ -1269,8 +1231,7 @@ ppp_ioctl(ppp_pcb *pcb, int cmd, void *arg)
  *  RETURN: >= 0 Number of characters written
  *           -1 Failed to write to device
  */
-int ppp_write(int pd, const u_char *s, int n) {
-  ppp_pcb *pc = &ppp_pcb_list[pd];
+int ppp_write(ppp_pcb *pcb, const u_char *s, int n) {
 #if PPPOS_SUPPORT
   u_char c;
   u_int fcs_out;
@@ -1278,8 +1239,8 @@ int ppp_write(int pd, const u_char *s, int n) {
 #endif /* PPPOS_SUPPORT */
 
 #if PPPOE_SUPPORT
-  if(pc->ethif) {
-    return ppp_write_over_ethernet(pd, s, n);
+  if(pcb->ethif) {
+    return ppp_write_over_ethernet(pcb, s, n);
   }
 #endif /* PPPOE_SUPPORT */
 
@@ -1288,7 +1249,7 @@ int ppp_write(int pd, const u_char *s, int n) {
   if (head == NULL) {
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.proterr);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return PPPERR_ALLOC;
   }
 
@@ -1296,10 +1257,10 @@ int ppp_write(int pd, const u_char *s, int n) {
 
   /* If the link has been idle, we'll send a fresh flag character to
    * flush any noise. */
-  if ((sys_jiffies() - pc->last_xmit) >= PPP_MAXIDLEFLAG) {
+  if ((sys_jiffies() - pcb->last_xmit) >= PPP_MAXIDLEFLAG) {
     tail = ppp_append(PPP_FLAG, tail, NULL);
   }
-  pc->last_xmit = sys_jiffies();
+  pcb->last_xmit = sys_jiffies();
 
   fcs_out = PPP_INITFCS;
   /* Load output buffer. */
@@ -1310,40 +1271,39 @@ int ppp_write(int pd, const u_char *s, int n) {
     fcs_out = PPP_FCS(fcs_out, c);
 
     /* Copy to output buffer escaping special characters. */
-    tail = ppp_append(c, tail, &pc->out_accm);
+    tail = ppp_append(c, tail, &pcb->out_accm);
   }
 
   /* Add FCS and trailing flag. */
   c = ~fcs_out & 0xFF;
-  tail = ppp_append(c, tail, &pc->out_accm);
+  tail = ppp_append(c, tail, &pcb->out_accm);
   c = (~fcs_out >> 8) & 0xFF;
-  tail = ppp_append(c, tail, &pc->out_accm);
+  tail = ppp_append(c, tail, &pcb->out_accm);
   tail = ppp_append(PPP_FLAG, tail, NULL);
 
   /* If we failed to complete the packet, throw it away.
    * Otherwise send it. */
   if (!tail) {
     PPPDEBUG(LOG_WARNING,
-             ("ppp_write[%d]: Alloc err - dropping pbuf len=%d\n", pd, head->len));
+             ("ppp_write[%d]: Alloc err - dropping pbuf len=%d\n", pcb->unit, head->len));
            /*"ppp_write[%d]: Alloc err - dropping %d:%.*H", pd, head->len, LWIP_MIN(head->len * 2, 40), head->payload)); */
     pbuf_free(head);
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.proterr);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return PPPERR_ALLOC;
   }
 
-  PPPDEBUG(LOG_INFO, ("ppp_write[%d]: len=%d\n", pd, head->len));
+  PPPDEBUG(LOG_INFO, ("ppp_write[%d]: len=%d\n", pcb->unit, head->len));
                    /* "ppp_write[%d]: %d:%.*H", pd, head->len, LWIP_MIN(head->len * 2, 40), head->payload)); */
-  pppos_put(pc, head);
+  pppos_put(pcb, head);
 #endif /* PPPOS_SUPPORT */
 
   return PPPERR_NONE;
 }
 
 #if PPPOE_SUPPORT
-static int ppp_write_over_ethernet(int pd, const u_char *s, int n) {
-  ppp_pcb *pc = &ppp_pcb_list[pd];
+static int ppp_write_over_ethernet(ppp_pcb *pcb, const u_char *s, int n) {
   struct pbuf *pb;
 
   /* skip address & flags */
@@ -1355,19 +1315,19 @@ static int ppp_write_over_ethernet(int pd, const u_char *s, int n) {
   if(!pb) {
     LINK_STATS_INC(link.memerr);
     LINK_STATS_INC(link.proterr);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return PPPERR_ALLOC;
   }
 
   pbuf_header(pb, -(s16_t)PPPOE_HDRLEN);
 
-  pc->last_xmit = sys_jiffies();
+  pcb->last_xmit = sys_jiffies();
 
   MEMCPY(pb->payload, s, n);
 
-  if(pppoe_xmit(pc->pppoe_sc, pb) != ERR_OK) {
+  if(pppoe_xmit(pcb->pppoe_sc, pb) != ERR_OK) {
     LINK_STATS_INC(link.err);
-    snmp_inc_ifoutdiscards(&pc->netif);
+    snmp_inc_ifoutdiscards(&pcb->netif);
     return PPPERR_DEVICE;
   }
 
@@ -1375,8 +1335,8 @@ static int ppp_write_over_ethernet(int pd, const u_char *s, int n) {
   dump_packet("sent", (unsigned char *)s, n);
 #endif /* PRINTPKT_SUPPORT */
 
-  snmp_add_ifoutoctets(&pc->netif, (u16_t)n);
-  snmp_inc_ifoutucastpkts(&pc->netif);
+  snmp_add_ifoutoctets(&pcb->netif, (u16_t)n);
+  snmp_inc_ifoutucastpkts(&pcb->netif);
   LINK_STATS_INC(link.xmit);
   return PPPERR_NONE;
 }
@@ -1711,36 +1671,34 @@ static void ppp_over_ethernet_link_status_cb(ppp_pcb *pcb, int state) {
 }
 #endif /* PPPOE_SUPPORT */
 
-void ppp_link_down(int pd) {
-  PPPDEBUG(LOG_DEBUG, ("ppp_link_down: unit %d\n", pd));
+void ppp_link_down(ppp_pcb *pcb) {
+  PPPDEBUG(LOG_DEBUG, ("ppp_link_down: unit %d\n", pcb->unit));
 
 #if PPPOS_SUPPORT && PPP_INPROC_OWNTHREAD
-  ppp_receive_wakeup(pd);
+  ppp_receive_wakeup(pcb);
 #endif /* PPPOS_SUPPORT && PPP_INPROC_OWNTHREAD*/
 }
 
-void ppp_link_terminated(int pd) {
-  PPPDEBUG(LOG_DEBUG, ("ppp_link_terminated: unit %d\n", pd));
+void ppp_link_terminated(ppp_pcb *pcb) {
+  PPPDEBUG(LOG_DEBUG, ("ppp_link_terminated: unit %d\n", pcb->unit));
 
 #if PPPOE_SUPPORT
-  if (ppp_pcb_list[pd].ethif) {
-    pppoe_disconnect(ppp_pcb_list[pd].pppoe_sc);
+  if (pcb->ethif) {
+    pppoe_disconnect(pcb->pppoe_sc);
   } else
 #endif /* PPPOE_SUPPORT */
   {
 #if PPPOS_SUPPORT
-    ppp_pcb* pc;
 #if PPP_INPROC_OWNTHREAD
-    ppp_receive_wakeup(pd);
+    ppp_receive_wakeup(pcb);
 #endif /* PPP_INPROC_OWNTHREAD */
-    pc = &ppp_pcb_list[pd];
 
-    PPPDEBUG(LOG_DEBUG, ("ppp_link_terminated: unit %d: link_status_cb=%p err_code=%d\n", pd, pc->link_status_cb, pc->err_code));
-    if (pc->link_status_cb) {
-      pc->link_status_cb(pc->link_status_ctx, pc->err_code ? pc->err_code : PPPERR_PROTOCOL, NULL);
+    PPPDEBUG(LOG_DEBUG, ("ppp_link_terminated: unit %d: link_status_cb=%p err_code=%d\n", pcb->unit, pcb->link_status_cb, pcb->err_code));
+    if (pcb->link_status_cb) {
+      pcb->link_status_cb(pcb->link_status_ctx, pcb->err_code ? pcb->err_code : PPPERR_PROTOCOL, NULL);
     }
 
-    pc->open_flag = 0;/**/
+    pcb->open_flag = 0;
 #endif /* PPPOS_SUPPORT */
   }
   PPPDEBUG(LOG_DEBUG, ("ppp_link_terminated: finished.\n"));
@@ -1785,9 +1743,8 @@ ppp_set_netif_linkcallback(ppp_pcb *pcb, netif_status_callback_fn link_callback)
 /*
  * new_phase - signal the start of a new phase of pppd's operation.
  */
-void new_phase(int unit, int p) {
-    ppp_pcb *pc = &ppp_pcb_list[unit];
-    pc->phase = p;
+void new_phase(ppp_pcb *pcb, int p) {
+    pcb->phase = p;
 #if PPP_NOTIFY
     /* The one willing notify support should add here the code to be notified of phase changes */
 #endif /* PPP_NOTIFY */
@@ -1797,20 +1754,19 @@ void new_phase(int unit, int p) {
  * ppp_send_config - configure the transmit-side characteristics of
  * the ppp interface.
  */
-int ppp_send_config(int unit, int mtu, u_int32_t accm, int pcomp, int accomp) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+int ppp_send_config(ppp_pcb *pcb, int mtu, u_int32_t accm, int pcomp, int accomp) {
 #if PPPOS_SUPPORT
   int i;
 #endif /* PPPOS_SUPPORT */
 
-  /* pc->mtu = mtu; -- set correctly with netif_set_mtu */
-  pc->pcomp = pcomp;
-  pc->accomp = accomp;
+  /* pcb->mtu = mtu; -- set correctly with netif_set_mtu */
+  pcb->pcomp = pcomp;
+  pcb->accomp = accomp;
 
 #if PPPOS_SUPPORT
   /* Load the ACCM bits for the 32 control codes. */
   for (i = 0; i < 32/8; i++) {
-    pc->out_accm[i] = (u_char)((accm >> (8 * i)) & 0xFF);
+    pcb->out_accm[i] = (u_char)((accm >> (8 * i)) & 0xFF);
   }
 #else
   LWIP_UNUSED_ARG(accm);
@@ -1818,10 +1774,10 @@ int ppp_send_config(int unit, int mtu, u_int32_t accm, int pcomp, int accomp) {
 
 #if PPPOS_SUPPORT
   PPPDEBUG(LOG_INFO, ("ppp_send_config[%d]: out_accm=%X %X %X %X\n",
-            unit,
-            pc->out_accm[0], pc->out_accm[1], pc->out_accm[2], pc->out_accm[3]));
+            pcb->unit,
+            pcb->out_accm[0], pcb->out_accm[1], pcb->out_accm[2], pcb->out_accm[3]));
 #else
-  PPPDEBUG(LOG_INFO, ("ppp_send_config[%d]\n", unit) );
+  PPPDEBUG(LOG_INFO, ("ppp_send_config[%d]\n", pcb->unit) );
 #endif /* PPPOS_SUPPORT */
   return 0;
 }
@@ -1830,9 +1786,8 @@ int ppp_send_config(int unit, int mtu, u_int32_t accm, int pcomp, int accomp) {
  * ppp_recv_config - configure the receive-side characteristics of
  * the ppp interface.
  */
-int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp) {
+int ppp_recv_config(ppp_pcb *pcb, int mru, u_int32_t accm, int pcomp, int accomp) {
 #if PPPOS_SUPPORT
-  ppp_pcb *pc = &ppp_pcb_list[unit];
   int i;
   SYS_ARCH_DECL_PROTECT(lev);
 #endif /* PPPOS_SUPPORT */
@@ -1846,7 +1801,7 @@ int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp) {
   SYS_ARCH_PROTECT(lev);
   for (i = 0; i < 32 / 8; i++) {
     /* @todo: does this work? ext_accm has been modified from pppd! */
-    pc->rx.in_accm[i] = (u_char)(accm >> (i * 8));
+    pcb->rx.in_accm[i] = (u_char)(accm >> (i * 8));
   }
   SYS_ARCH_UNPROTECT(lev);
 #else
@@ -1855,10 +1810,10 @@ int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp) {
 
 #if PPPOS_SUPPORT
   PPPDEBUG(LOG_INFO, ("ppp_recv_config[%d]: in_accm=%X %X %X %X\n",
-            unit,
-            pc->rx.in_accm[0], pc->rx.in_accm[1], pc->rx.in_accm[2], pc->rx.in_accm[3]));
+            pcb->unit,
+            pcb->rx.in_accm[0], pcb->rx.in_accm[1], pcb->rx.in_accm[2], pcb->rx.in_accm[3]));
 #else
-  PPPDEBUG(LOG_INFO, ("ppp_recv_config[%d]\n", unit) );
+  PPPDEBUG(LOG_INFO, ("ppp_recv_config[%d]\n", pcb->unit) );
 #endif /* PPPOS_SUPPORT */
   return 0;
 }
@@ -1867,20 +1822,18 @@ int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp) {
 /*
  * sifaddr - Config the interface IP addresses and netmask.
  */
-int sifaddr (int unit, u_int32_t our_adr, u_int32_t his_adr,
+int sifaddr(ppp_pcb *pcb, u_int32_t our_adr, u_int32_t his_adr,
 	     u_int32_t net_mask) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
 
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("sifaddr[%d]: bad params\n", unit));
-  } else {
-    SMEMCPY(&pc->addrs.our_ipaddr, &our_adr, sizeof(our_adr));
-    SMEMCPY(&pc->addrs.his_ipaddr, &his_adr, sizeof(his_adr));
-    SMEMCPY(&pc->addrs.netmask, &net_mask, sizeof(net_mask));
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("sifaddr[%d]: bad params\n", pcb->unit));
+    return 0;
   }
-  return st;
+
+  SMEMCPY(&pcb->addrs.our_ipaddr, &our_adr, sizeof(our_adr));
+  SMEMCPY(&pcb->addrs.his_ipaddr, &his_adr, sizeof(his_adr));
+  SMEMCPY(&pcb->addrs.netmask, &net_mask, sizeof(net_mask));
+  return 1;
 }
 
 
@@ -1889,39 +1842,36 @@ int sifaddr (int unit, u_int32_t our_adr, u_int32_t his_adr,
  * cifaddr - Clear the interface IP addresses, and delete routes
  * through the interface if possible.
  */
-int cifaddr (int unit, u_int32_t our_adr, u_int32_t his_adr) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int cifaddr(ppp_pcb *pcb, u_int32_t our_adr, u_int32_t his_adr) {
 
   LWIP_UNUSED_ARG(our_adr);
   LWIP_UNUSED_ARG(his_adr);
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("cifaddr[%d]: bad params\n", unit));
-  } else {
-    IP4_ADDR(&pc->addrs.our_ipaddr, 0,0,0,0);
-    IP4_ADDR(&pc->addrs.his_ipaddr, 0,0,0,0);
-    IP4_ADDR(&pc->addrs.netmask, 255,255,255,255);
+
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("cifaddr[%d]: bad params\n", pcb->unit));
+    return 0;
   }
-  return st;
+
+  IP4_ADDR(&pcb->addrs.our_ipaddr, 0,0,0,0);
+  IP4_ADDR(&pcb->addrs.his_ipaddr, 0,0,0,0);
+  IP4_ADDR(&pcb->addrs.netmask, 255,255,255,255);
+  return 1;
 }
 
 
 /*
  * sdns - Config the DNS servers
  */
-int sdns (int unit, u_int32_t ns1, u_int32_t ns2) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int sdns(ppp_pcb *pcb, u_int32_t ns1, u_int32_t ns2) {
 
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("sdns[%d]: bad params\n", unit));
-  } else {
-    SMEMCPY(&pc->addrs.dns1, &ns1, sizeof(ns1));
-    SMEMCPY(&pc->addrs.dns2, &ns2, sizeof(ns2));
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("sdns[%d]: bad params\n", pcb->unit));
+    return 0;
   }
-  return st;
+
+  SMEMCPY(&pcb->addrs.dns1, &ns1, sizeof(ns1));
+  SMEMCPY(&pcb->addrs.dns2, &ns2, sizeof(ns2));
+  return 1;
 }
 
 
@@ -1929,53 +1879,48 @@ int sdns (int unit, u_int32_t ns1, u_int32_t ns2) {
  *
  * cdns - Clear the DNS servers
  */
-int cdns (int unit, u_int32_t ns1, u_int32_t ns2) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int cdns(ppp_pcb *pcb, u_int32_t ns1, u_int32_t ns2) {
 
   LWIP_UNUSED_ARG(ns1);
   LWIP_UNUSED_ARG(ns2);
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("cdns[%d]: bad params\n", unit));
-  } else {
-    IP4_ADDR(&pc->addrs.dns1, 0,0,0,0);
-    IP4_ADDR(&pc->addrs.dns2, 0,0,0,0);
+
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("cdns[%d]: bad params\n", pcb->unit));
+    return 0;
   }
-  return st;
+
+  IP4_ADDR(&pcb->addrs.dns1, 0,0,0,0);
+  IP4_ADDR(&pcb->addrs.dns2, 0,0,0,0);
+  return 1;
 }
 
 
 /*
  * sifup - Config the interface up and enable IP packets to pass.
  */
-int sifup(int u)
-{
-  ppp_pcb *pc = &ppp_pcb_list[u];
-  int st = 1;
+int sifup(ppp_pcb *pcb) {
 
-  if (u < 0 || u >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad params\n", u));
-  } else {
-    netif_remove(&pc->netif);
-    if (netif_add(&pc->netif, &pc->addrs.our_ipaddr, &pc->addrs.netmask,
-                  &pc->addrs.his_ipaddr, (void *)(size_t)u, ppp_netif_init_cb, ip_input)) {
-      netif_set_up(&pc->netif);
-      pc->if_up = 1;
-      pc->err_code = PPPERR_NONE;
-
-      PPPDEBUG(LOG_DEBUG, ("sifup: unit %d: link_status_cb=%p err_code=%d\n", u, pc->link_status_cb, pc->err_code));
-      if (pc->link_status_cb) {
-        pc->link_status_cb(pc->link_status_ctx, pc->err_code, &pc->addrs);
-      }
-    } else {
-      st = 0;
-      PPPDEBUG(LOG_ERR, ("sifup[%d]: netif_add failed\n", u));
-    }
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad params\n", pcb->unit));
+    return 0;
   }
 
-  return st;
+  netif_remove(&pcb->netif);
+  if (!netif_add(&pcb->netif, &pcb->addrs.our_ipaddr, &pcb->addrs.netmask,
+                &pcb->addrs.his_ipaddr, (void *)pcb, ppp_netif_init_cb, ip_input)) {
+    PPPDEBUG(LOG_ERR, ("sifup[%d]: netif_add failed\n", pcb->unit));
+    return 0;
+  }
+
+  netif_set_up(&pcb->netif);
+  pcb->if_up = 1;
+  pcb->err_code = PPPERR_NONE;
+
+  PPPDEBUG(LOG_DEBUG, ("sifup: unit %d: link_status_cb=%p err_code=%d\n", pcb->unit, pcb->link_status_cb, pcb->err_code));
+  if (pcb->link_status_cb)
+    pcb->link_status_cb(pcb->link_status_ctx, pcb->err_code, &pcb->addrs);
+
+  return 1;
 }
 
 /********************************************************************
@@ -1983,31 +1928,29 @@ int sifup(int u)
  * sifdown - Disable the indicated protocol and config the interface
  *	     down if there are no remaining protocols.
  */
-int sifdown(int unit) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int sifdown(ppp_pcb *pcb) {
 
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("sifdown[%d]: bad params\n", unit));
-  } else {
-    pc->if_up = 0;
-    /* make sure the netif status callback is called */
-    netif_set_down(&pc->netif);
-    netif_remove(&pc->netif);
-    PPPDEBUG(LOG_DEBUG, ("sifdown: unit %d: link_status_cb=%p err_code=%d\n", unit, pc->link_status_cb, pc->err_code));
-    if (pc->link_status_cb) {
-      pc->link_status_cb(pc->link_status_ctx, PPPERR_CONNECT, NULL);
-    }
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("sifdown[%d]: bad params\n", pcb->unit));
+    return 0;
   }
-  return st;
+
+  pcb->if_up = 0;
+  /* make sure the netif status callback is called */
+  netif_set_down(&pcb->netif);
+  netif_remove(&pcb->netif);
+  PPPDEBUG(LOG_DEBUG, ("sifdown: unit %d: link_status_cb=%p err_code=%d\n", pcb->unit, pcb->link_status_cb, pcb->err_code));
+  if (pcb->link_status_cb)
+    pcb->link_status_cb(pcb->link_status_ctx, PPPERR_CONNECT, NULL);
+
+  return 1;
 }
 
 /*
  * sifnpmode - Set the mode for handling packets for a given NP.
  */
-int sifnpmode(int u, int proto, enum NPmode mode) {
-  LWIP_UNUSED_ARG(u);
+int sifnpmode(ppp_pcb *pcb, int proto, enum NPmode mode) {
+  LWIP_UNUSED_ARG(pcb);
   LWIP_UNUSED_ARG(proto);
   LWIP_UNUSED_ARG(mode);
   return 0;
@@ -2016,27 +1959,25 @@ int sifnpmode(int u, int proto, enum NPmode mode) {
 /*
  * netif_set_mtu - set the MTU on the PPP network interface.
  */
-void netif_set_mtu(int unit, int mtu) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+void netif_set_mtu(ppp_pcb *pcb, int mtu) {
 
   /* Validate parameters. */
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag)
+  if(!pcb->open_flag)
     return;
 
-  pc->mtu = mtu;
+  pcb->mtu = mtu;
 }
 
 /*
  * netif_get_mtu - get PPP interface MTU
  */
-int netif_get_mtu(int unit) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
+int netif_get_mtu(ppp_pcb *pcb) {
 
   /* Validate parameters. */
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag)
-    return  0;
+  if(!pcb->open_flag)
+    return 0;
 
-  return pc->mtu;
+  return pcb->mtu;
 }
 
 /********************************************************************
@@ -2051,45 +1992,37 @@ int netif_get_mtu(int unit) {
  * and then changes the temporary addresses to the addresses for the real
  * ppp connection when it has come up.
  */
-int sifdefaultroute(int unit, u_int32_t ouraddr, u_int32_t gateway, bool replace) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int sifdefaultroute(ppp_pcb *pcb, u_int32_t ouraddr, u_int32_t gateway, bool replace) {
 
   LWIP_UNUSED_ARG(ouraddr);
   LWIP_UNUSED_ARG(gateway);
   LWIP_UNUSED_ARG(replace);
 
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("sifdefaultroute[%d]: bad params\n", unit));
-  } else {
-    netif_set_default(&pc->netif);
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("sifdefaultroute[%d]: bad params\n", pcb->unit));
+    return 0;
   }
 
-  /* TODO: check how PPP handled the netMask, previously not set by ipSetDefault */
-
-  return st;
+  netif_set_default(&pcb->netif);
+  return 1;
 }
 
 /********************************************************************
  *
  * cifdefaultroute - delete a default route through the address given.
  */
-int cifdefaultroute(int unit, u_int32_t ouraddr, u_int32_t gateway) {
-  ppp_pcb *pc = &ppp_pcb_list[unit];
-  int st = 1;
+int cifdefaultroute(ppp_pcb *pcb, u_int32_t ouraddr, u_int32_t gateway) {
 
   LWIP_UNUSED_ARG(ouraddr);
   LWIP_UNUSED_ARG(gateway);
 
-  if (unit < 0 || unit >= NUM_PPP || !pc->open_flag) {
-    st = 0;
-    PPPDEBUG(LOG_WARNING, ("cifdefaultroute[%d]: bad params\n", unit));
-  } else {
-    netif_set_default(NULL);
+  if(!pcb->open_flag) {
+    PPPDEBUG(LOG_WARNING, ("cifdefaultroute[%d]: bad params\n", pcb->unit));
+    return 0;
   }
 
-  return st;
+  netif_set_default(NULL);
+  return 1;
 }
 
 /********************************************************************
@@ -2097,9 +2030,11 @@ int cifdefaultroute(int unit, u_int32_t ouraddr, u_int32_t gateway) {
  * sifproxyarp - Make a proxy ARP entry for the peer.
  */
 
-int sifproxyarp(int unit, u_int32_t his_adr) {
-    /* FIXME: do we really need that in IPCP ? */
-    return 0;
+int sifproxyarp(ppp_pcb *pcb, u_int32_t his_adr) {
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(his_adr);
+  /* FIXME: do we really need that in IPCP ? */
+  return 0;
 }
 
 /********************************************************************
@@ -2107,26 +2042,27 @@ int sifproxyarp(int unit, u_int32_t his_adr) {
  * cifproxyarp - Delete the proxy ARP entry for the peer.
  */
 
-int cifproxyarp(int unit, u_int32_t his_adr) {
-   /* FIXME: do we really need that in IPCP ? */
-   return 0;
+int cifproxyarp(ppp_pcb *pcb, u_int32_t his_adr) {
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(his_adr);
+  /* FIXME: do we really need that in IPCP ? */
+  return 0;
 }
 
 /********************************************************************
  *
  * sifvjcomp - config tcp header compression
  */
-int sifvjcomp(int u, int vjcomp, int cidcomp, int maxcid) {
-#if PPPOS_SUPPORT && VJ_SUPPORT
-  ppp_pcb *pc = &ppp_pcb_list[u];
+int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid) {
 
-  pc->vj_enabled = vjcomp;
-  pc->vj_comp.compressSlot = cidcomp;
-  pc->vj_comp.maxSlotIndex = maxcid;
+#if PPPOS_SUPPORT && VJ_SUPPORT
+  pcb->vj_enabled = vjcomp;
+  pcb->vj_comp.compressSlot = cidcomp;
+  pcb->vj_comp.maxSlotIndex = maxcid;
   PPPDEBUG(LOG_INFO, ("sifvjcomp: VJ compress enable=%d slot=%d max slot=%d\n",
             vjcomp, cidcomp, maxcid));
 #else /* PPPOS_SUPPORT && VJ_SUPPORT */
-  LWIP_UNUSED_ARG(u);
+  LWIP_UNUSED_ARG(pcb);
   LWIP_UNUSED_ARG(vjcomp);
   LWIP_UNUSED_ARG(cidcomp);
   LWIP_UNUSED_ARG(maxcid);
@@ -2139,9 +2075,9 @@ int sifvjcomp(int u, int vjcomp, int cidcomp, int maxcid) {
  *
  * get_idle_time - return how long the link has been idle.
  */
-int get_idle_time(int u, struct ppp_idle *ip) {
+int get_idle_time(ppp_pcb *pcb, struct ppp_idle *ip) {
     /* FIXME: add idle time support and make it optional */
-    LWIP_UNUSED_ARG(u);
+    LWIP_UNUSED_ARG(pcb);
     LWIP_UNUSED_ARG(ip);
     return 1;
 }
diff --git a/src/netif/ppp/ppp.h b/src/netif/ppp/ppp.h
index c2339d02..27a82b6f 100644
--- a/src/netif/ppp/ppp.h
+++ b/src/netif/ppp/ppp.h
@@ -45,6 +45,35 @@
 #include "lwip/sys.h"
 #include "lwip/timers.h"
 
+#include "vj.h"
+
+
+/** PPP_INPROC_MULTITHREADED==1 call ppp_input using tcpip_callback().
+ * Set this to 0 if pppos_input_proc is called inside tcpip_thread or with NO_SYS==1.
+ * Default is 1 for NO_SYS==0 (multithreaded) and 0 for NO_SYS==1 (single-threaded).
+ */
+#ifndef PPP_INPROC_MULTITHREADED
+#define PPP_INPROC_MULTITHREADED (NO_SYS==0)
+#endif
+
+/** PPP_INPROC_OWNTHREAD==1: start a dedicated RX thread per PPP session.
+ * Default is 0: call pppos_input() for received raw characters, character
+ * reception is up to the port */
+#ifndef PPP_INPROC_OWNTHREAD
+#define PPP_INPROC_OWNTHREAD      PPP_INPROC_MULTITHREADED
+#endif
+
+#if PPP_INPROC_OWNTHREAD && !PPP_INPROC_MULTITHREADED
+  #error "PPP_INPROC_OWNTHREAD needs PPP_INPROC_MULTITHREADED==1"
+#endif
+
+#if PPPOS_SUPPORT
+/** RX buffer size: this may be configured smaller! */
+#ifndef PPPOS_RX_BUFSIZE
+#define PPPOS_RX_BUFSIZE    (PPP_MRU + PPP_HDRLEN)
+#endif
+#endif /* PPPOS_SUPPORT */
+
 
 #ifndef __u_char_defined
 
@@ -61,6 +90,12 @@ typedef unsigned char  u_char;
 *** PUBLIC DEFINITIONS ***
 *************************/
 
+/*
+ * The basic PPP frame.
+ */
+#define PPP_HDRLEN	4	/* octets for standard ppp header */
+#define PPP_FCSLEN	2	/* octets for FCS */
+
 /* Error codes. */
 #define PPPERR_NONE      0 /* No error. */
 #define PPPERR_PARAM    -1 /* Invalid parameter. */
@@ -135,7 +170,25 @@ struct ppp_addrs {
   ip_addr_t our_ipaddr, his_ipaddr, netmask, dns1, dns2;
 };
 
+/* FIXME: find a way to move ppp_dev_states and ppp_pcb_rx_s to ppp_impl.h */
 #if PPPOS_SUPPORT
+/*
+ * Extended asyncmap - allows any character to be escaped.
+ */
+typedef u_char  ext_accm[32];
+
+/* PPP packet parser states.  Current state indicates operation yet to be
+ * completed. */
+typedef enum {
+  PDIDLE = 0,  /* Idle state - waiting. */
+  PDSTART,     /* Process start flag. */
+  PDADDRESS,   /* Process address field. */
+  PDCONTROL,   /* Process control field. */
+  PDPROTOCOL1, /* Process protocol field 1. */
+  PDPROTOCOL2, /* Process protocol field 2. */
+  PDDATA       /* Process data byte. */
+} ppp_dev_states;
+
 /*
  * PPP interface RX control block.
  */
diff --git a/src/netif/ppp/ppp_impl.h b/src/netif/ppp/ppp_impl.h
index f84690b2..d10af710 100644
--- a/src/netif/ppp/ppp_impl.h
+++ b/src/netif/ppp/ppp_impl.h
@@ -69,9 +69,6 @@ typedef unsigned char	bool;
 /*
  * The basic PPP frame.
  */
-#define PPP_HDRLEN	4	/* octets for standard ppp header */
-#define PPP_FCSLEN	2	/* octets for FCS */
-
 #define PPP_ADDRESS(p)	(((u_char *)(p))[0])
 #define PPP_CONTROL(p)	(((u_char *)(p))[1])
 #define PPP_PROTOCOL(p)	((((u_char *)(p))[2] << 8) + ((u_char *)(p))[3])
@@ -155,11 +152,6 @@ typedef unsigned short  u_int16_t;
 #endif
 #endif
 
-/*
- * Extended asyncmap - allows any character to be escaped.
- */
-typedef u_char  ext_accm[32];
-
 /*
  * What to do with network protocol (NP) packets.
  */
@@ -312,7 +304,7 @@ struct protent {
      */
     /* Process a received data packet */
     void (*datainput) (int unit, u_char *pkt, int len);
-    bool enabled_flag;		/* 0 iff protocol is disabled */
+    bool enabled_flag;		/* 0 if protocol is disabled */
 #if PRINTPKT_SUPPORT
     char *name;			/* Text name of protocol */
     char *data_name;		/* Text name of corresponding data protocol */
@@ -396,17 +388,16 @@ ppp_pcb ppp_pcb_list[NUM_PPP]; /* The PPP interface control blocks. */
 /* PPP flow functions
  */
 #if PPPOE_SUPPORT
-void ppp_over_ethernet_init_failed(int pd);
 /* function called by pppoe.c */
 void ppp_input_over_ethernet(ppp_pcb *pcb, struct pbuf *pb);
 #endif /* PPPOE_SUPPORT */
 
 /* function called by all PPP subsystems to send packets */
-int ppp_write(int pd, const u_char *s, int n);
+int ppp_write(ppp_pcb *pcb, const u_char *s, int n);
 
 /* functions called by auth.c link_terminated() */
-void ppp_link_down(int pd);
-void ppp_link_terminated(int pd);
+void ppp_link_down(ppp_pcb *pcb);
+void ppp_link_terminated(ppp_pcb *pcb);
 
 /* merge a pbuf chain into one pbuf */
 struct pbuf * ppp_singlebuf(struct pbuf *p);
@@ -415,37 +406,37 @@ struct pbuf * ppp_singlebuf(struct pbuf *p);
 /* Functions called by various PPP subsystems to configure
  * the PPP interface or change the PPP phase.
  */
-void new_phase(int unit, int p);
+void new_phase(ppp_pcb *pcb, int p);
 
 #if PPPOS_SUPPORT
-void ppp_set_xaccm(int unit, ext_accm *accm);
+void ppp_set_xaccm(ppp_pcb *pcb, ext_accm *accm);
 #endif /* PPPOS_SUPPORT */
-int ppp_send_config(int unit, int mtu, u_int32_t accm, int pcomp, int accomp);
-int ppp_recv_config(int unit, int mru, u_int32_t accm, int pcomp, int accomp);
+int ppp_send_config(ppp_pcb *pcb, int mtu, u_int32_t accm, int pcomp, int accomp);
+int ppp_recv_config(ppp_pcb *pcb, int mru, u_int32_t accm, int pcomp, int accomp);
 
-int sifaddr(int unit, u_int32_t our_adr, u_int32_t his_adr, u_int32_t net_mask);
-int cifaddr(int unit, u_int32_t our_adr, u_int32_t his_adr);
+int sifaddr(ppp_pcb *pcb, u_int32_t our_adr, u_int32_t his_adr, u_int32_t net_mask);
+int cifaddr(ppp_pcb *pcb, u_int32_t our_adr, u_int32_t his_adr);
 
-int sdns(int unit, u_int32_t ns1, u_int32_t ns2);
-int cdns(int unit, u_int32_t ns1, u_int32_t ns2);
+int sdns(ppp_pcb *pcb, u_int32_t ns1, u_int32_t ns2);
+int cdns(ppp_pcb *pcb, u_int32_t ns1, u_int32_t ns2);
 
-int sifup(int u);
-int sifdown (int u);
+int sifup(ppp_pcb *pcb);
+int sifdown (ppp_pcb *pcb);
 
-int sifnpmode(int u, int proto, enum NPmode mode);
+int sifnpmode(ppp_pcb *pcb, int proto, enum NPmode mode);
 
-void netif_set_mtu(int unit, int mtu);
-int netif_get_mtu(int unit);
+void netif_set_mtu(ppp_pcb *pcb, int mtu);
+int netif_get_mtu(ppp_pcb *pcb);
 
-int sifdefaultroute (int unit, u_int32_t ouraddr, u_int32_t gateway, bool replace);
-int cifdefaultroute (int unit, u_int32_t ouraddr, u_int32_t gateway);
+int sifdefaultroute(ppp_pcb *pcb, u_int32_t ouraddr, u_int32_t gateway, bool replace);
+int cifdefaultroute(ppp_pcb *pcb, u_int32_t ouraddr, u_int32_t gateway);
 
-int sifproxyarp (int unit, u_int32_t his_adr);
-int cifproxyarp (int unit, u_int32_t his_adr);
+int sifproxyarp(ppp_pcb *pcb, u_int32_t his_adr);
+int cifproxyarp(ppp_pcb *pcb, u_int32_t his_adr);
 
-int sifvjcomp (int u, int vjcomp, int cidcomp, int maxcid);
+int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid);
 
-int get_idle_time(int u, struct ppp_idle *ip);
+int get_idle_time(ppp_pcb *pcb, struct ppp_idle *ip);
 
 int get_loop_output(void);
 
diff --git a/src/netif/ppp/upap.c b/src/netif/ppp/upap.c
index cd8d2c2b..8f471920 100644
--- a/src/netif/ppp/upap.c
+++ b/src/netif/ppp/upap.c
@@ -584,6 +584,7 @@ static void
 upap_sauthreq(u)
     upap_state *u;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[u->us_unit];
     u_char *outp;
     int outlen;
 
@@ -602,7 +603,7 @@ upap_sauthreq(u)
     PUTCHAR(u->us_passwdlen, outp);
     MEMCPY(outp, u->us_passwd, u->us_passwdlen);
 
-    ppp_write(u->us_unit, outpacket_buf, outlen + PPP_HDRLEN);
+    ppp_write(pcb, outpacket_buf, outlen + PPP_HDRLEN);
 
     TIMEOUT(upap_timeout, u, u->us_timeouttime);
     ++u->us_transmits;
@@ -620,6 +621,7 @@ upap_sresp(u, code, id, msg, msglen)
     char *msg;
     int msglen;
 {
+    ppp_pcb *pcb = &ppp_pcb_list[u->us_unit];
     u_char *outp;
     int outlen;
 
@@ -632,7 +634,7 @@ upap_sresp(u, code, id, msg, msglen)
     PUTSHORT(outlen, outp);
     PUTCHAR(msglen, outp);
     MEMCPY(outp, msg, msglen);
-    ppp_write(u->us_unit, outpacket_buf, outlen + PPP_HDRLEN);
+    ppp_write(pcb, outpacket_buf, outlen + PPP_HDRLEN);
 }
 #endif /* UNUSED */