diff --git a/src/vnet/udp/udp_encap.c b/src/vnet/udp/udp_encap.c
index cb93adb..a0f5a50 100644
--- a/src/vnet/udp/udp_encap.c
+++ b/src/vnet/udp/udp_encap.c
@@ -47,8 +47,7 @@
 udp_encap_restack (udp_encap_t * ue)
 {
   dpo_stack (udp_encap_dpo_types[ue->ue_ip_proto],
-	     fib_proto_to_dpo (ue->ue_ip_proto),
-	     &ue->ue_dpo,
+	     fib_proto_to_dpo (ue->ue_ip_proto), &ue->ue_dpo,
 	     fib_entry_contribute_ip_forwarding (ue->ue_fib_entry_index));
 }
 
@@ -325,12 +324,12 @@
 }
 
 const static char *const udp4_encap_ip4_nodes[] = {
-  "udp4-encap",
+  "udp4o4-encap",
   NULL,
 };
 
 const static char *const udp4_encap_ip6_nodes[] = {
-  "udp4-encap",
+  "udp6o4-encap",
   NULL,
 };
 
@@ -345,12 +344,12 @@
 };
 
 const static char *const udp6_encap_ip4_nodes[] = {
-  "udp6-encap",
+  "udp4o6-encap",
   NULL,
 };
 
 const static char *const udp6_encap_ip6_nodes[] = {
-  "udp6-encap",
+  "udp6o6-encap",
   NULL,
 };
 
diff --git a/src/vnet/udp/udp_encap.h b/src/vnet/udp/udp_encap.h
index b096e0f..648e3b5 100644
--- a/src/vnet/udp/udp_encap.h
+++ b/src/vnet/udp/udp_encap.h
@@ -85,7 +85,7 @@
   /**
    * The second cacheline contains control-plane data
    */
-    CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
 
   /**
    * linkage into the FIB graph
diff --git a/src/vnet/udp/udp_encap_node.c b/src/vnet/udp/udp_encap_node.c
index 5b9fc0b..1ebe795 100644
--- a/src/vnet/udp/udp_encap_node.c
+++ b/src/vnet/udp/udp_encap_node.c
@@ -61,9 +61,9 @@
 }
 
 always_inline uword
-udp_encap_inline (vlib_main_t * vm,
-		  vlib_node_runtime_t * node,
-		  vlib_frame_t * frame, int is_encap_v6)
+udp_encap_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
+		  vlib_frame_t *frame, ip_address_family_t encap_family,
+		  ip_address_family_t payload_family)
 {
   vlib_combined_counter_main_t *cm = &udp_encap_counters;
   u32 *from = vlib_frame_vector_args (frame);
@@ -121,12 +121,13 @@
 	  ue1 = udp_encap_get (uei1);
 
 	  /* Paint */
-	  if (is_encap_v6)
+	  if (encap_family == AF_IP6)
 	    {
 	      const u8 n_bytes =
 		sizeof (udp_header_t) + sizeof (ip6_header_t);
-	      ip_udp_encap_two (vm, b0, b1, (u8 *) & ue0->ue_hdrs,
-				(u8 *) & ue1->ue_hdrs, n_bytes, 0);
+	      ip_udp_encap_two (vm, b0, b1, (u8 *) &ue0->ue_hdrs,
+				(u8 *) &ue1->ue_hdrs, n_bytes, encap_family,
+				payload_family);
 	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 		{
 		  udp6_encap_trace_t *tr =
@@ -147,9 +148,9 @@
 	      const u8 n_bytes =
 		sizeof (udp_header_t) + sizeof (ip4_header_t);
 
-	      ip_udp_encap_two (vm, b0, b1,
-				(u8 *) & ue0->ue_hdrs,
-				(u8 *) & ue1->ue_hdrs, n_bytes, 1);
+	      ip_udp_encap_two (vm, b0, b1, (u8 *) &ue0->ue_hdrs,
+				(u8 *) &ue1->ue_hdrs, n_bytes, encap_family,
+				payload_family);
 
 	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 		{
@@ -202,12 +203,12 @@
 									b0));
 
 	  /* Paint */
-	  if (is_encap_v6)
+	  if (encap_family == AF_IP6)
 	    {
 	      const u8 n_bytes =
 		sizeof (udp_header_t) + sizeof (ip6_header_t);
-	      ip_udp_encap_one (vm, b0, (u8 *) & ue0->ue_hdrs.ip6, n_bytes,
-				0);
+	      ip_udp_encap_one (vm, b0, (u8 *) &ue0->ue_hdrs.ip6, n_bytes,
+				encap_family, payload_family);
 
 	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 		{
@@ -222,8 +223,8 @@
 	      const u8 n_bytes =
 		sizeof (udp_header_t) + sizeof (ip4_header_t);
 
-	      ip_udp_encap_one (vm, b0, (u8 *) & ue0->ue_hdrs.ip4, n_bytes,
-				1);
+	      ip_udp_encap_one (vm, b0, (u8 *) &ue0->ue_hdrs.ip4, n_bytes,
+				encap_family, payload_family);
 
 	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 		{
@@ -248,37 +249,87 @@
   return frame->n_vectors;
 }
 
-VLIB_NODE_FN (udp4_encap_node) (vlib_main_t * vm,
-				vlib_node_runtime_t * node,
-				vlib_frame_t * frame)
+VLIB_NODE_FN (udp4o4_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 {
-  return udp_encap_inline (vm, node, frame, 0);
+  return udp_encap_inline (vm, node, frame, AF_IP4, AF_IP4);
 }
 
-VLIB_NODE_FN (udp6_encap_node) (vlib_main_t * vm,
-				vlib_node_runtime_t * node,
-				vlib_frame_t * frame)
+VLIB_NODE_FN (udp6o4_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
 {
-  return udp_encap_inline (vm, node, frame, 1);
+  return udp_encap_inline (vm, node, frame, AF_IP4, AF_IP6);
+}
+
+VLIB_NODE_FN (udp4_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return udp_encap_inline (vm, node, frame, AF_IP4, N_AF);
+}
+
+VLIB_NODE_FN (udp6o6_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return udp_encap_inline (vm, node, frame, AF_IP6, AF_IP6);
+}
+
+VLIB_NODE_FN (udp4o6_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return udp_encap_inline (vm, node, frame, AF_IP6, AF_IP4);
+}
+
+VLIB_NODE_FN (udp6_encap_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return udp_encap_inline (vm, node, frame, AF_IP6, N_AF);
 }
 
 /* *INDENT-OFF* */
+VLIB_REGISTER_NODE (udp4o4_encap_node) = {
+  .name = "udp4o4-encap",
+  .vector_size = sizeof (u32),
+  .format_trace = format_udp4_encap_trace,
+  .n_next_nodes = 0,
+};
+
+VLIB_REGISTER_NODE (udp6o4_encap_node) = {
+  .name = "udp6o4-encap",
+  .vector_size = sizeof (u32),
+  .format_trace = format_udp6_encap_trace,
+  .n_next_nodes = 0,
+  .sibling_of = "udp4o4-encap",
+};
+
 VLIB_REGISTER_NODE (udp4_encap_node) = {
   .name = "udp4-encap",
   .vector_size = sizeof (u32),
-
   .format_trace = format_udp4_encap_trace,
-
   .n_next_nodes = 0,
+  .sibling_of = "udp4o4-encap",
+};
+
+VLIB_REGISTER_NODE (udp6o6_encap_node) = {
+  .name = "udp6o6-encap",
+  .vector_size = sizeof (u32),
+  .format_trace = format_udp6_encap_trace,
+  .n_next_nodes = 0,
+};
+
+VLIB_REGISTER_NODE (udp4o6_encap_node) = {
+  .name = "udp4o6-encap",
+  .vector_size = sizeof (u32),
+  .format_trace = format_udp4_encap_trace,
+  .n_next_nodes = 0,
+  .sibling_of = "udp6o6-encap",
 };
 
 VLIB_REGISTER_NODE (udp6_encap_node) = {
   .name = "udp6-encap",
   .vector_size = sizeof (u32),
-
   .format_trace = format_udp6_encap_trace,
-
   .n_next_nodes = 0,
+  .sibling_of = "udp6o6-encap",
 };
 /* *INDENT-ON* */
 
diff --git a/src/vnet/udp/udp_inlines.h b/src/vnet/udp/udp_inlines.h
index e4eb0c8..d79dc9a 100644
--- a/src/vnet/udp/udp_inlines.h
+++ b/src/vnet/udp/udp_inlines.h
@@ -97,14 +97,20 @@
 }
 
 always_inline void
-ip_udp_encap_one (vlib_main_t * vm, vlib_buffer_t * b0, u8 * ec0, word ec_len,
-		  u8 is_ip4)
+ip_udp_encap_one (vlib_main_t *vm, vlib_buffer_t *b0, u8 *ec0, word ec_len,
+		  ip_address_family_t encap_family,
+		  ip_address_family_t payload_family)
 {
-  vnet_calc_checksums_inline (vm, b0, is_ip4, !is_ip4);
+
+  if (payload_family < N_AF)
+    {
+      vnet_calc_checksums_inline (vm, b0, payload_family == AF_IP4,
+				  payload_family == AF_IP6);
+    }
 
   vlib_buffer_advance (b0, -ec_len);
 
-  if (is_ip4)
+  if (encap_family == AF_IP4)
     {
       ip4_header_t *ip0;
 
@@ -127,21 +133,27 @@
 }
 
 always_inline void
-ip_udp_encap_two (vlib_main_t * vm, vlib_buffer_t * b0, vlib_buffer_t * b1,
-		  u8 * ec0, u8 * ec1, word ec_len, u8 is_v4)
+ip_udp_encap_two (vlib_main_t *vm, vlib_buffer_t *b0, vlib_buffer_t *b1,
+		  u8 *ec0, u8 *ec1, word ec_len,
+		  ip_address_family_t encap_family,
+		  ip_address_family_t payload_family)
 {
   u16 new_l0, new_l1;
   udp_header_t *udp0, *udp1;
+  int payload_ip4 = (payload_family == AF_IP4);
 
   ASSERT (_vec_len (ec0) == _vec_len (ec1));
 
-  vnet_calc_checksums_inline (vm, b0, is_v4, !is_v4);
-  vnet_calc_checksums_inline (vm, b1, is_v4, !is_v4);
+  if (payload_family < N_AF)
+    {
+      vnet_calc_checksums_inline (vm, b0, payload_ip4, !payload_ip4);
+      vnet_calc_checksums_inline (vm, b1, payload_ip4, !payload_ip4);
+    }
 
   vlib_buffer_advance (b0, -ec_len);
   vlib_buffer_advance (b1, -ec_len);
 
-  if (is_v4)
+  if (encap_family == AF_IP4)
     {
       ip4_header_t *ip0, *ip1;
       ip_csum_t sum0, sum1;