diff --git a/net/sixlowpan/sixlowpan_tcpsend.c b/net/sixlowpan/sixlowpan_tcpsend.c
index a7a1a90f3b5..2b0ce15cb33 100644
--- a/net/sixlowpan/sixlowpan_tcpsend.c
+++ b/net/sixlowpan/sixlowpan_tcpsend.c
@@ -50,10 +50,73 @@
 #include "netdev/netdev.h"
 #include "socket/socket.h"
 #include "tcp/tcp.h"
+#include "utils/utils.h"
 #include "sixlowpan/sixlowpan_internal.h"
 
 #if defined(CONFIG_NET_6LOWPAN) && defined(CONFIG_NET_TCP)
 
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: sixlowpan_tcp_chksum
+ *
+ * Description:
+ *   Perform the checksum calcaultion over the IPv6, protocol headers, and
+ *   data payload as necessary.
+ *
+ * Input Parameters:
+ *   ipv6tcp - A reference to a structure containing the IPv6 and TCP headers.
+ *   buf     - The beginning of the payload data
+ *   buflen  - The length of the payload data.
+ *
+ * Returned Value:
+ *   The calculated checksum
+ *
+ ****************************************************************************/
+
+static uint16_t sixlowpan_tcp_chksum(FAR struct ipv6tcp_hdr_s *ipv6tcp,
+                                     FAR const uint8_t *buf, uint16_t buflen)
+{
+  uint16_t upperlen;
+  uint16_t sum;
+
+  /* The length reported in the IPv6 header is the length of the payload
+   * that follows the header.
+   */
+
+  upperlen = ((uint16_t)ipv6tcp->ipv6.len[0] << 8) + ipv6tcp->ipv6.len[1];
+
+  /* Verify some minimal assumptions */
+
+  if (upperlen > CONFIG_NET_6LOWPAN_MTU)
+    {
+      return 0;
+    }
+
+  /* The checksum is calculated starting with a pseudo-header of IPv6 header
+   * fields according to the IPv6 standard, which consists of the source
+   * and destination addresses, the packet length and the next header field.
+   */
+
+  sum = upperlen + ipv6tcp->ipv6.proto;
+
+  /* Sum IP source and destination addresses. */
+
+  sum = chksum(sum, (FAR uint8_t *)ipv6tcp->ipv6.srcipaddr,
+               2 * sizeof(net_ipv6addr_t));
+
+  /* Sum the TCP header */
+
+  sum = chksum(sum, (FAR uint8_t *)&ipv6tcp->tcp, TCP_HDRLEN);
+
+  /* Sum payload data. */
+
+  sum = chksum(sum, buf, buflen);
+  return (sum == 0) ? 0xffff : htons(sum);
+}
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -224,19 +287,14 @@ ssize_t psock_6lowpan_tcp_send(FAR struct socket *psock, FAR const void *buf,
   /* Calculate TCP checksum. */
 
   ipv6tcp.tcp.tcpchksum   = 0;
-#if 0
-  /* REVISIT: Current checksum logic expects the IPv6 header, the UDP header, and
-   * the payload data to be in contiguous memory.
-   */
-
-  ipv6tcp.tcp.tcpchksum   = ~tcp_ipv6_chksum(dev);
-#endif
+  ipv6tcp.tcp.tcpchksum   = ~sixlowpan_tcp_chksum(&ipv6tcp, buf, buflen);
 
   ninfo("Outgoing TCP packet length: %d bytes\n", iplen + IOPv6_HDRLEN);
 
 #ifdef CONFIG_NET_STATISTICS
   g_netstats.tcp.sent++;
 #endif
+
   /* Set the socket state to sending */
 
   psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_SEND);
diff --git a/net/sixlowpan/sixlowpan_udpsend.c b/net/sixlowpan/sixlowpan_udpsend.c
index 49932514c81..61fbe3b237a 100644
--- a/net/sixlowpan/sixlowpan_udpsend.c
+++ b/net/sixlowpan/sixlowpan_udpsend.c
@@ -51,10 +51,75 @@
 #include "netdev/netdev.h"
 #include "socket/socket.h"
 #include "udp/udp.h"
+#include "utils/utils.h"
 #include "sixlowpan/sixlowpan_internal.h"
 
 #if defined(CONFIG_NET_6LOWPAN) && defined(CONFIG_NET_UDP)
 
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: sixlowpan_udp_chksum
+ *
+ * Description:
+ *   Perform the checksum calcaultion over the IPv6, protocol headers, and
+ *   data payload as necessary.
+ *
+ * Input Parameters:
+ *   ipv6udp - A reference to a structure containing the IPv6 and UDP headers.
+ *   buf     - The beginning of the payload data
+ *   buflen  - The length of the payload data.
+ *
+ * Returned Value:
+ *   The calculated checksum
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_UDP_CHECKSUMS
+static uint16_t sixlowpan_udp_chksum(FAR struct ipv6udp_hdr_s *ipv6udp,
+                                     FAR const uint8_t *buf, uint16_t buflen)
+{
+  uint16_t upperlen;
+  uint16_t sum;
+
+  /* The length reported in the IPv6 header is the length of the payload
+   * that follows the header.
+   */
+
+  upperlen = ((uint16_t)ipv6udp->ipv6.len[0] << 8) + ipv6udp->ipv6.len[1];
+
+  /* Verify some minimal assumptions */
+
+  if (upperlen > CONFIG_NET_6LOWPAN_MTU)
+    {
+      return 0;
+    }
+
+  /* The checksum is calculated starting with a pseudo-header of IPv6 header
+   * fields according to the IPv6 standard, which consists of the source
+   * and destination addresses, the packet length and the next header field.
+   */
+
+  sum = upperlen + ipv6udp->ipv6.proto;
+
+  /* Sum IP source and destination addresses. */
+
+  sum = chksum(sum, (FAR uint8_t *)ipv6udp->ipv6.srcipaddr,
+               2 * sizeof(net_ipv6addr_t));
+
+  /* Sum the UDP header */
+
+  sum = chksum(sum, (FAR uint8_t *)&ipv6udp->udp, UDP_HDRLEN);
+
+  /* Sum payload data. */
+
+  sum = chksum(sum, buf, buflen);
+  return (sum == 0) ? 0xffff : htons(sum);
+}
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -211,23 +276,13 @@ ssize_t psock_6lowpan_udp_sendto(FAR struct socket *psock,
   ipv6udp.udp.udplen      = htons(iplen);
   ipv6udp.udp.udpchksum   = 0;
 
-  ipv6udp.udp.udpchksum   = 0;
-
-#warning Missing logic
-#if 0 /* REVISIT */
 #ifdef CONFIG_NET_UDP_CHECKSUMS
-  /* Calculate UDP checksum. */
-  /* REVISIT: Current checksum logic expects the IPv6 header, the UDP header, and
-   * the payload data to be in contiguous memory.
-   */
-
-  ipv6udp.udp.udpchksum   = ~udp_ipv6_chksum(dev);
+  ipv6udp.udp.udpchksum   = ~sixlowpan_udp_chksum(ipv6udp, buf, buflen);
   if (ipv6udp.udp.udpchksum == 0)
     {
       ipv6udp.udp.udpchksum = 0xffff;
     }
 #endif /* CONFIG_NET_UDP_CHECKSUMS */
-#endif /* REVISIT */
 
   ninfo("Outgoing UDP packet length: %d\n", iplen + IPv6_HDRLEN);
 
diff --git a/net/utils/Make.defs b/net/utils/Make.defs
index 270b80bbbe8..daad84805ea 100644
--- a/net/utils/Make.defs
+++ b/net/utils/Make.defs
@@ -1,7 +1,7 @@
 ############################################################################
 # net/utils/Make.defs
 #
-#   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+#   Copyright (C) 2014, 2017 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
 #
 # Redistribution and use in source and binary forms, with or without
@@ -36,7 +36,7 @@
 # Common utilities
 
 NET_CSRCS += net_dsec2tick.c net_dsec2timeval.c net_timeval2dsec.c
-NET_CSRCS += net_chksum.c net_lock.c
+NET_CSRCS += net_chksum.c net_ipchksum.c net_incr32.c net_lock.c
 
 # IPv6 utilities
 
@@ -44,6 +44,26 @@ ifeq ($(CONFIG_NET_IPv6),y)
 NET_CSRCS += net_ipv6_maskcmp.c net_ipv6_mask2pref.c net_ipv6_pref2mask.c
 endif
 
+# TCP utilities
+
+ifeq ($(CONFIG_NET_TCP),y)
+NET_CSRCS += net_tcpchksum.c
+endif
+
+# UDP utilities
+
+ifeq ($(CONFIG_NET_UDP),y)
+NET_CSRCS += net_udpchksum.c
+endif
+
+# ICMP utilities
+
+ifeq ($(CONFIG_NET_ICMP),y)
+NET_CSRCS += net_icmpchksum.c
+else ifeq ($(CONFIG_NET_ICMPv6),y)
+NET_CSRCS += net_icmpchksum.c
+endif
+
 # Include utility build support
 
 DEPPATH += --dep-path utils
diff --git a/net/utils/net_chksum.c b/net/utils/net_chksum.c
index 9f4055c7564..65272387759 100644
--- a/net/utils/net_chksum.c
+++ b/net/utils/net_chksum.c
@@ -56,19 +56,31 @@
 
 #define IPv4BUF   ((struct ipv4_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
 #define IPv6BUF   ((struct ipv6_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
-#define ICMPBUF   ((struct icmp_iphdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
-#define ICMPv6BUF ((struct icmp_ipv6hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
 
 /****************************************************************************
- * Private Functions
+ * Public Functions
  ****************************************************************************/
 
 /****************************************************************************
  * Name: chksum
+ *
+ * Description:
+ *   Calculate the raw change some over the memory region described by
+ *   data and len.
+ *
+ * Input Parameters:
+ *   sum  - Partial calculations carried over from a previous call to chksum().
+ *          This should be zero on the first time that check sum is called.
+ *   data - Beginning of the data to include in the checksum.
+ *   len  - Length of the data to include in the checksum.
+ *
+ * Returned Value:
+ *   The updated checksum value.
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_NET_ARCH_CHKSUM
-static uint16_t chksum(uint16_t sum, FAR const uint8_t *data, uint16_t len)
+uint16_t chksum(uint16_t sum, FAR const uint8_t *data, uint16_t len)
 {
   FAR const uint8_t *dataptr;
   FAR const uint8_t *last_byte;
@@ -107,158 +119,6 @@ static uint16_t chksum(uint16_t sum, FAR const uint8_t *data, uint16_t len)
 }
 #endif /* CONFIG_NET_ARCH_CHKSUM */
 
-/****************************************************************************
- * Name: ipv4_upperlayer_chksum
- ****************************************************************************/
-
-#if !defined(CONFIG_NET_ARCH_CHKSUM) && defined(CONFIG_NET_IPv4)
-static uint16_t ipv4_upperlayer_chksum(FAR struct net_driver_s *dev,
-                                       uint8_t proto)
-{
-  FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
-  uint16_t upperlen;
-  uint16_t sum;
-
-  /* The length reported in the IPv4 header is the length of both the IPv4
-   * header and the payload that follows the header.  We need to subtract
-   * the size of the IPv4 header to get the size of the payload.
-   */
-
-  upperlen = (((uint16_t)(ipv4->len[0]) << 8) + ipv4->len[1]) - IPv4_HDRLEN;
-
-  /* Verify some minimal assumptions */
-
-  if (upperlen > NET_DEV_MTU(dev))
-    {
-      return 0;
-    }
-
-  /* First sum pseudo-header. */
-  /* IP protocol and length fields. This addition cannot carry. */
-
-  sum = upperlen + proto;
-
-  /* Sum IP source and destination addresses. */
-
-  sum = chksum(sum, (FAR uint8_t *)&ipv4->srcipaddr, 2 * sizeof(in_addr_t));
-
-  /* Sum IP payload data. */
-
-  sum = chksum(sum, &dev->d_buf[IPv4_HDRLEN + NET_LL_HDRLEN(dev)], upperlen);
-  return (sum == 0) ? 0xffff : htons(sum);
-}
-#endif /* CONFIG_NET_ARCH_CHKSUM */
-
-/****************************************************************************
- * Name: ipv6_upperlayer_chksum
- ****************************************************************************/
-
-#if !defined(CONFIG_NET_ARCH_CHKSUM) && defined(CONFIG_NET_IPv6)
-static uint16_t ipv6_upperlayer_chksum(FAR struct net_driver_s *dev,
-                                       uint8_t proto)
-{
-  FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
-  uint16_t upperlen;
-  uint16_t sum;
-
-  /* The length reported in the IPv6 header is the length of the payload
-   * that follows the header.
-   */
-
-  upperlen = ((uint16_t)ipv6->len[0] << 8) + ipv6->len[1];
-
-  /* Verify some minimal assumptions */
-
-  if (upperlen > NET_DEV_MTU(dev))
-    {
-      return 0;
-    }
-
-  /* The checksum is calculated starting with a pseudo-header of IPv6 header
-   * fields according to the IPv6 standard, which consists of the source
-   * and destination addresses, the packet length and the next header field.
-   */
-
-  sum = upperlen + proto;
-
-  /* Sum IP source and destination addresses. */
-
-  sum = chksum(sum, (FAR uint8_t *)&ipv6->srcipaddr, 2 * sizeof(net_ipv6addr_t));
-
-  /* Sum IP payload data. */
-
-  sum = chksum(sum, &dev->d_buf[IPv6_HDRLEN + NET_LL_HDRLEN(dev)], upperlen);
-  return (sum == 0) ? 0xffff : htons(sum);
-}
-#endif /* CONFIG_NET_ARCH_CHKSUM */
-
-/****************************************************************************
- * Name: net_carry32
- *
- * Description:
- *   Calculate the Internet checksum over a buffer.
- *
- ****************************************************************************/
-
-#ifndef CONFIG_NET_ARCH_INCR32
-static inline void net_carry32(FAR uint8_t *sum, uint16_t op16)
-{
-  if (sum[2] < (op16 >> 8))
-    {
-      ++sum[1];
-      if (sum[1] == 0)
-        {
-          ++sum[0];
-        }
-    }
-
-  if (sum[3] < (op16 & 0xff))
-    {
-      ++sum[2];
-      if (sum[2] == 0)
-        {
-          ++sum[1];
-          if (sum[1] == 0)
-            {
-              ++sum[0];
-            }
-        }
-    }
-}
-#endif /* CONFIG_NET_ARCH_INCR32 */
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: net_incr32
- *
- * Description:
- *
- *   Carry out a 32-bit addition.
- *
- *   By defining CONFIG_NET_ARCH_INCR32, the architecture can replace
- *   net_incr32 with hardware assisted solutions.
- *
- * Input Parameters:
- *   op32 - A pointer to a 4-byte array representing a 32-bit integer in
- *          network byte order (big endian).  This value may not be word
- *          aligned. The value pointed to by op32 is modified in place
- *
- *   op16 - A 16-bit integer in host byte order.
- *
- ****************************************************************************/
-
-#ifndef CONFIG_NET_ARCH_INCR32
-void net_incr32(FAR uint8_t *op32, uint16_t op16)
-{
-  op32[3] += (op16 & 0xff);
-  op32[2] += (op16 >> 8);
-  net_carry32(op32, op16);
-}
-#endif /* CONFIG_NET_ARCH_INCR32 */
-
 /****************************************************************************
  * Name: net_chksum
  *
@@ -291,141 +151,4 @@ uint16_t net_chksum(FAR uint16_t *data, uint16_t len)
 }
 #endif /* CONFIG_NET_ARCH_CHKSUM */
 
-/****************************************************************************
- * Name: ipv4_chksum
- *
- * Description:
- *   Calculate the IPv4 header checksum of the packet header in d_buf.
- *
- *   The IPv4 header checksum is the Internet checksum of the 20 bytes of
- *   the IPv4 header.
- *
- *   If CONFIG_NET_ARCH_CHKSUM is defined, then this function must be
- *   provided by architecture-specific logic.
- *
- * Returned Value:
- *   The IPv4 header checksum of the IPv4 header in the d_buf buffer.
- *
- ****************************************************************************/
-
-#if defined(CONFIG_NET_IPv4) && !defined(CONFIG_NET_ARCH_CHKSUM)
-uint16_t ipv4_chksum(FAR struct net_driver_s *dev)
-{
-  uint16_t sum;
-
-  sum = chksum(0, &dev->d_buf[NET_LL_HDRLEN(dev)], IPv4_HDRLEN);
-  return (sum == 0) ? 0xffff : htons(sum);
-}
-#endif /* CONFIG_NET_ARCH_CHKSUM */
-
-/****************************************************************************
- * Name: tcp_chksum, tcp_ipv4_chksum, and tcp_ipv6_chksum
- *
- * Description:
- *   Calculate the TCP checksum of the packet in d_buf and d_appdata.
- *
- *   The TCP checksum is the Internet checksum of data contents of the
- *   TCP segment, and a pseudo-header as defined in RFC793.
- *
- *   Note: The d_appdata pointer that points to the packet data may
- *   point anywhere in memory, so it is not possible to simply calculate
- *   the Internet checksum of the contents of the d_buf buffer.
- *
- * Returned Value:
- *   The TCP checksum of the TCP segment in d_buf and pointed to by
- *   d_appdata.
- *
- ****************************************************************************/
-
-#ifndef CONFIG_NET_ARCH_CHKSUM
-#ifdef CONFIG_NET_IPv4
-uint16_t tcp_ipv4_chksum(FAR struct net_driver_s *dev)
-{
-  return ipv4_upperlayer_chksum(dev, IP_PROTO_TCP);
-}
-#endif /* CONFIG_NET_IPv4 */
-
-#ifdef CONFIG_NET_IPv6
-uint16_t tcp_ipv6_chksum(FAR struct net_driver_s *dev)
-{
-  return ipv6_upperlayer_chksum(dev, IP_PROTO_TCP);
-}
-#endif /* CONFIG_NET_IPv6 */
-#endif /* !CONFIG_NET_ARCH_CHKSUM */
-
-#if defined(CONFIG_NET_IPv4) && defined(CONFIG_NET_IPv6)
-uint16_t tcp_chksum(FAR struct net_driver_s *dev)
-{
-  if (IFF_IS_IPv6(dev->d_flags))
-    {
-      return tcp_ipv6_chksum(dev);
-    }
-  else
-    {
-      return tcp_ipv4_chksum(dev);
-    }
-}
-#endif
-
-/****************************************************************************
- * Name: udp_ipv4_chksum
- *
- * Description:
- *   Calculate the UDP/IPv4 checksum of the packet in d_buf and d_appdata.
- *
- ****************************************************************************/
-
-#if defined(CONFIG_NET_UDP_CHECKSUMS) && defined(CONFIG_NET_IPv4)
-uint16_t udp_ipv4_chksum(FAR struct net_driver_s *dev)
-{
-  return ipv4_upperlayer_chksum(dev, IP_PROTO_UDP);
-}
-#endif
-
-/****************************************************************************
- * Name: udp_ipv6_chksum
- *
- * Description:
- *   Calculate the UDP/IPv6 checksum of the packet in d_buf and d_appdata.
- *
- ****************************************************************************/
-
-#if defined(CONFIG_NET_UDP_CHECKSUMS) && defined(CONFIG_NET_IPv6)
-uint16_t udp_ipv6_chksum(FAR struct net_driver_s *dev)
-{
-  return ipv6_upperlayer_chksum(dev, IP_PROTO_UDP);
-}
-#endif
-
-/****************************************************************************
- * Name: icmp_chksum
- *
- * Description:
- *   Calculate the checksum of the ICMP message
- *
- ****************************************************************************/
-
-#if defined(CONFIG_NET_ICMP) && defined(CONFIG_NET_ICMP_PING)
-uint16_t icmp_chksum(FAR struct net_driver_s *dev, int len)
-{
-  FAR struct icmp_iphdr_s *icmp = ICMPBUF;
-  return net_chksum((FAR uint16_t *)&icmp->type, len);
-}
-#endif /* CONFIG_NET_ICMP && CONFIG_NET_ICMP_PING */
-
-/****************************************************************************
- * Name: icmpv6_chksum
- *
- * Description:
- *   Calculate the checksum of the ICMPv6 message
- *
- ****************************************************************************/
-
-#ifdef CONFIG_NET_ICMPv6
-uint16_t icmpv6_chksum(FAR struct net_driver_s *dev)
-{
-  return ipv6_upperlayer_chksum(dev, IP_PROTO_ICMP6);
-}
-#endif
-
 #endif /* CONFIG_NET */
diff --git a/net/utils/utils.h b/net/utils/utils.h
index 6e33b72a83b..ffeca8c3f69 100644
--- a/net/utils/utils.h
+++ b/net/utils/utils.h
@@ -191,6 +191,99 @@ uint8_t net_ipv6_mask2pref(FAR const uint16_t *mask);
 void net_ipv6_pref2mask(uint8_t preflen, net_ipv6addr_t mask);
 #endif
 
+/****************************************************************************
+ * Name: chksum
+ *
+ * Description:
+ *   Calculate the raw change some over the memory region described by
+ *   data and len.
+ *
+ * Input Parameters:
+ *   sum  - Partial calculations carried over from a previous call to chksum().
+ *          This should be zero on the first time that check sum is called.
+ *   data - Beginning of the data to include in the checksum.
+ *   len  - Length of the data to include in the checksum.
+ *
+ * Returned Value:
+ *   The updated checksum value.
+ *
+ ****************************************************************************/
+
+#ifndef CONFIG_NET_ARCH_CHKSUM
+uint16_t chksum(uint16_t sum, FAR const uint8_t *data, uint16_t len);
+#endif
+
+/****************************************************************************
+ * Name: net_chksum
+ *
+ * Description:
+ *   Calculate the Internet checksum over a buffer.
+ *
+ *   The Internet checksum is the one's complement of the one's complement
+ *   sum of all 16-bit words in the buffer.
+ *
+ *   See RFC1071.
+ *
+ *   If CONFIG_NET_ARCH_CHKSUM is defined, then this function must be
+ *   provided by architecture-specific logic.
+ *
+ * Input Parameters:
+ *
+ *   buf - A pointer to the buffer over which the checksum is to be computed.
+ *
+ *   len - The length of the buffer over which the checksum is to be computed.
+ *
+ * Returned Value:
+ *   The Internet checksum of the buffer.
+ *
+ ****************************************************************************/
+
+#ifndef CONFIG_NET_ARCH_CHKSUM
+uint16_t net_chksum(FAR uint16_t *data, uint16_t len);
+#endif
+
+/****************************************************************************
+ * Name: ipv4_upperlayer_chksum
+ *
+ * Description:
+ *   Perform the checksum calcaultion over the IPv4, protocol headers, and
+ *   data payload as necessary.
+ *
+ * Input Parameters:
+ *   dev   - The network driver instance.  The packet data is in the d_buf
+ *           of the device.
+ *   proto - The protocol being supported
+ *
+ * Returned Value:
+ *   The calculated checksum
+ *
+ ****************************************************************************/
+
+#if !defined(CONFIG_NET_ARCH_CHKSUM) && defined(CONFIG_NET_IPv4)
+uint16_t ipv4_upperlayer_chksum(FAR struct net_driver_s *dev, uint8_t proto);
+#endif
+
+/****************************************************************************
+ * Name: ipv6_upperlayer_chksum
+ *
+ * Description:
+ *   Perform the checksum calcaultion over the IPv6, protocol headers, and
+ *   data payload as necessary.
+ *
+ * Input Parameters:
+ *   dev   - The network driver instance.  The packet data is in the d_buf
+ *           of the device.
+ *   proto - The protocol being supported
+ *
+ * Returned Value:
+ *   The calculated checksum
+ *
+ ****************************************************************************/
+
+#if !defined(CONFIG_NET_ARCH_CHKSUM) && defined(CONFIG_NET_IPv6)
+uint16_t ipv6_upperlayer_chksum(FAR struct net_driver_s *dev, uint8_t proto);
+#endif
+
 /****************************************************************************
  * Name: tcp_chksum, tcp_ipv4_chksum, and tcp_ipv6_chksum
  *