diff --git a/net/sixlowpan/sixlowpan_hc06.c b/net/sixlowpan/sixlowpan_hc06.c
index 7981142d39..97f56e85ca 100644
--- a/net/sixlowpan/sixlowpan_hc06.c
+++ b/net/sixlowpan/sixlowpan_hc06.c
@@ -878,91 +878,133 @@ void sixlowpan_compresshdr_hc06(FAR struct ieee802154_driver_s *ieee,
 
   g_uncomp_hdrlen = IPv6_HDRLEN;
 
-#ifdef CONFIG_NET_UDP
-  /* UDP header compression */
+  /* Add protocol header */
 
-  if (ipv6->proto == IP_PROTO_UDP)
+  switch (ipv6->proto)
     {
-      /* The UDP header will follow the IPv6 header */
+#ifdef CONFIG_NET_UDP
+      /* UDP header compression */
 
-      FAR struct udp_hdr_s *udp =
-        (FAR struct udp_hdr_s *)((FAR uint8_t *)ipv6 + IPv6_HDRLEN);
-
-      ninfo("Uncompressed UDP ports: srcport=%04x destport=%04x\n",
-            ntohs(udp->srcport), ntohs(udp->destport));
-
-      /* Mask out the last 4 bits can be used as a mask */
-
-      if (((ntohs(udp->srcport) & 0xfff0) == SIXLOWPAN_UDP_4_BIT_PORT_MIN) &&
-          ((ntohs(udp->destport) & 0xfff0) == SIXLOWPAN_UDP_4_BIT_PORT_MIN))
+      case IP_PROTO_UDP:
         {
-          /* We can compress 12 bits of both source and dest */
+          /* The UDP header will follow the IPv6 header */
 
-          *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_11;
+          FAR struct udp_hdr_s *udp =
+            (FAR struct udp_hdr_s *)((FAR uint8_t *)ipv6 + IPv6_HDRLEN);
 
-          ninfo("Remove 12b of both source & dest with prefix 0xf0b*\n");
+          ninfo("Uncompressed UDP ports: srcport=%04x destport=%04x\n",
+                ntohs(udp->srcport), ntohs(udp->destport));
 
-          *(g_hc06ptr + 1) =
-            (uint8_t)((ntohs(udp->srcport) - SIXLOWPAN_UDP_4_BIT_PORT_MIN) << 4) +
-            (uint8_t)((ntohs(udp->destport) - SIXLOWPAN_UDP_4_BIT_PORT_MIN));
+          /* Mask out the last 4 bits can be used as a mask */
 
-          g_hc06ptr += 2;
+          if (((ntohs(udp->srcport) & 0xfff0) == SIXLOWPAN_UDP_4_BIT_PORT_MIN) &&
+              ((ntohs(udp->destport) & 0xfff0) == SIXLOWPAN_UDP_4_BIT_PORT_MIN))
+            {
+              /* We can compress 12 bits of both source and dest */
+
+              *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_11;
+
+              ninfo("Remove 12b of both source & dest with prefix 0xf0b*\n");
+
+              *(g_hc06ptr + 1) =
+                (uint8_t)((ntohs(udp->srcport) - SIXLOWPAN_UDP_4_BIT_PORT_MIN) << 4) +
+                (uint8_t)((ntohs(udp->destport) - SIXLOWPAN_UDP_4_BIT_PORT_MIN));
+
+              g_hc06ptr += 2;
+            }
+          else if ((ntohs(udp->destport) & 0xff00) ==
+                   SIXLOWPAN_UDP_8_BIT_PORT_MIN)
+            {
+              /* We can compress 8 bits of dest, leave source. */
+
+              *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_01;
+
+              ninfo("Leave source, remove 8 bits of dest with prefix 0xF0\n");
+
+              memcpy(g_hc06ptr + 1, &udp->srcport, 2);
+              *(g_hc06ptr + 3) =
+                (uint8_t) ((ntohs(udp->destport) -
+                            SIXLOWPAN_UDP_8_BIT_PORT_MIN));
+              g_hc06ptr += 4;
+            }
+          else if ((ntohs(udp->srcport) & 0xff00) ==
+                   SIXLOWPAN_UDP_8_BIT_PORT_MIN)
+            {
+              /* We can compress 8 bits of src, leave dest. Copy compressed port */
+
+              *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_10;
+
+              ninfo("Remove 8 bits of source with prefix 0xF0, leave dest. hch: %u\n",
+                    *g_hc06ptr);
+
+              *(g_hc06ptr + 1) =
+                (uint8_t)((ntohs(udp->srcport) - SIXLOWPAN_UDP_8_BIT_PORT_MIN));
+
+              memcpy(g_hc06ptr + 2, &udp->destport, 2);
+              g_hc06ptr += 4;
+            }
+          else
+            {
+              /* we cannot compress. Copy uncompressed ports, full checksum */
+
+              *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_00;
+
+              nwarn("WARNING: Cannot compress headers\n");
+
+              memcpy(g_hc06ptr + 1, &udp->srcport, 4);
+              g_hc06ptr += 5;
+            }
+
+          /* Always inline the checksum */
+
+          if (1)
+            {
+              memcpy(g_hc06ptr, &udp->udpchksum, 2);
+              g_hc06ptr += 2;
+            }
+
+          g_uncomp_hdrlen += UDP_HDRLEN;
         }
-      else if ((ntohs(udp->destport) & 0xff00) ==
-               SIXLOWPAN_UDP_8_BIT_PORT_MIN)
-        {
-          /* We can compress 8 bits of dest, leave source. */
-
-          *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_01;
-
-          ninfo("Leave source, remove 8 bits of dest with prefix 0xF0\n");
-
-          memcpy(g_hc06ptr + 1, &udp->srcport, 2);
-          *(g_hc06ptr + 3) =
-            (uint8_t) ((ntohs(udp->destport) -
-                        SIXLOWPAN_UDP_8_BIT_PORT_MIN));
-          g_hc06ptr += 4;
-        }
-      else if ((ntohs(udp->srcport) & 0xff00) ==
-               SIXLOWPAN_UDP_8_BIT_PORT_MIN)
-        {
-          /* We can compress 8 bits of src, leave dest. Copy compressed port */
-
-          *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_10;
-
-          ninfo("Remove 8 bits of source with prefix 0xF0, leave dest. hch: %u\n",
-                *g_hc06ptr);
-
-          *(g_hc06ptr + 1) =
-            (uint8_t)((ntohs(udp->srcport) - SIXLOWPAN_UDP_8_BIT_PORT_MIN));
-
-          memcpy(g_hc06ptr + 2, &udp->destport, 2);
-          g_hc06ptr += 4;
-        }
-      else
-        {
-          /* we cannot compress. Copy uncompressed ports, full checksum */
-
-          *g_hc06ptr = SIXLOWPAN_NHC_UDP_CS_P_00;
-
-          nwarn("WARNING: Cannot compress headers\n");
-
-          memcpy(g_hc06ptr + 1, &udp->srcport, 4);
-          g_hc06ptr += 5;
-        }
-
-      /* Always inline the checksum */
-
-      if (1)
-        {
-          memcpy(g_hc06ptr, &udp->udpchksum, 2);
-          g_hc06ptr += 2;
-        }
-
-      g_uncomp_hdrlen += UDP_HDRLEN;
-    }
+        break;
 #endif /* CONFIG_NET_UDP */
 
+#ifdef CONFIG_NET_TCP
+      /* TCP header -- not compressed */
+
+      case IP_PROTO_TCP:
+        {
+          FAR struct tcp_hdr_s *tcp =
+            (FAR struct tcp_hdr_s *)((FAR uint8_t *)ipv6 + IPv6_HDRLEN);
+          unsigned int hdrsize;
+
+          hdrsize = ((uint16_t)tcp->tcpoffset >> 4) << 2;
+          memcpy(g_hc06ptr, tcp, hdrsize);
+
+          g_uncomp_hdrlen += hdrsize;
+          g_hc06ptr       += hdrsize;
+        }
+        break;
+#endif
+
+#ifdef CONFIG_NET_ICMPv6
+      /* TCP header -- not compressed */
+
+      case IP_PROTO_ICMP:
+        {
+          FAR const uint8_t *src = (FAR const uint8_t *)ipv6 + IPv6_HDRLEN;
+
+          memcpy(g_hc06ptr, src, ICMPv6_HDRLEN)
+          g_uncomp_hdrlen += ICMPv6_HDRLEN;
+          g_hc06ptr       += ICMPv6_HDRLEN;
+        }
+        break;
+#endif
+
+      default:
+        nerr("ERROR: Unsupported protocol: %02x\n", ipv6->proto);
+        break;
+    }
+
   /* Before the g_frame_hdrlen operation */
 
   iphc[0] = iphc0;
@@ -1199,7 +1241,7 @@ void sixlowpan_uncompresshdr_hc06(FAR const struct ieee802154_data_ind_s *ind,
     }
   else
     {
-      /* no multicast */
+      /* No multicast */
       /* Context based */
 
       if ((iphc1 & SIXLOWPAN_IPHC_DAC) != 0)
diff --git a/net/sixlowpan/sixlowpan_tcpsend.c b/net/sixlowpan/sixlowpan_tcpsend.c
index d05f8650fa..d79a1f8a65 100644
--- a/net/sixlowpan/sixlowpan_tcpsend.c
+++ b/net/sixlowpan/sixlowpan_tcpsend.c
@@ -475,13 +475,15 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
     {
       uint32_t seqno;
       uint16_t winleft;
+      uint16_t sndlen;
 
       DEBUGASSERT((flags & WPAN_POLL) != 0);
 
-      /* Get the amount of data that we can send in the next packet */
-
-      uint32_t sndlen = sinfo->s_buflen - sinfo->s_sent;
+      /* Get the amount of TCP payload data that we can send in the next
+       * packet.
+       */
 
+      sndlen = sinfo->s_buflen - sinfo->s_sent;
       if (sndlen > conn->mss)
         {
           sndlen = conn->mss;
@@ -493,8 +495,8 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
           sndlen = winleft;
         }
 
-      ninfo("s_buflen=%u s_sent=%u mss=%u winsize=%u\n",
-            sinfo->s_buflen, sinfo->s_sent, conn->mss, conn->winsize);
+      ninfo("s_buflen=%u s_sent=%u mss=%u winsize=%u sndlen=%d\n",
+            sinfo->s_buflen, sinfo->s_sent, conn->mss, conn->winsize, sndlen);
 
       if (sndlen > 0)
         {
@@ -506,7 +508,9 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
            */
 
           seqno = sinfo->s_sent + sinfo->s_isn;
-          ninfo("SEND: sndseq %08x->%08x\n", conn->sndseq, seqno);
+          ninfo("Sending: sndseq %08lx->%08x\n",
+                (unsigned long)tcp_getsequence(conn->sndseq), seqno);
+
           tcp_setsequence(conn->sndseq, seqno);
 
           /* Create the IPv6 + TCP header */
diff --git a/wireless/ieee802154/mac802154_loopback.c b/wireless/ieee802154/mac802154_loopback.c
index 6e32b64b14..81b81e4b44 100644
--- a/wireless/ieee802154/mac802154_loopback.c
+++ b/wireless/ieee802154/mac802154_loopback.c
@@ -131,16 +131,6 @@ static uint8_t g_panid[IEEE802154_PANIDSIZE] =
   0xca, 0xfe
 };
 
-static const uint8_t g_src_eaddr[IEEE802154_EADDRSIZE] =
-{
-  0x0a, 0xfa, 0xde, 0x00, 0xde, 0xad, 0xbe, 0xef
-};
-
-static const uint8_t g_src_saddr[IEEE802154_SADDRSIZE] =
-{
-  0x12, 0x34
-};
-
 /****************************************************************************
  * Private Function Prototypes
  ****************************************************************************/
@@ -311,13 +301,11 @@ static int lo_loopback(FAR struct net_driver_s *dev)
   ind.dest.mode = IEEE802154_ADDRMODE_SHORT;
 #endif
 
-  /* Only loopback the local address is the destination and some (arbitrary)
-   * address is the source.
-   */
+  /* On loopback the local address is both the source and destination. */
 
   IEEE802154_PANIDCOPY(ind.src.panid, g_panid);
-  IEEE802154_SADDRCOPY(ind.src.saddr, g_src_saddr);
-  IEEE802154_EADDRCOPY(ind.src.eaddr, g_src_eaddr);
+  IEEE802154_SADDRCOPY(ind.src.saddr, g_saddr);
+  IEEE802154_EADDRCOPY(ind.src.eaddr, g_eaddr);
 
   IEEE802154_PANIDCOPY(ind.dest.panid, g_panid);
   IEEE802154_SADDRCOPY(ind.dest.saddr, g_saddr);