diff --git a/common/utils/itti_analyzer/libparser/enum_type.c b/common/utils/itti_analyzer/libparser/enum_type.c
index 5cc91c0ae0..063872dfa6 100644
--- a/common/utils/itti_analyzer/libparser/enum_type.c
+++ b/common/utils/itti_analyzer/libparser/enum_type.c
@@ -11,7 +11,7 @@ char *enum_type_get_name_from_value(struct types_s *type, uint32_t value)
     char    *enum_name = "UNKNOWN";
     types_t *enum_value;
 
-    /* Loop on eache enumeration values */
+    /* Loop on each enumeration values */
     for (enum_value = type->child; enum_value; enum_value = enum_value->next) {
         if (value == enum_value->init_value) {
             enum_name = enum_value->name;
@@ -34,6 +34,7 @@ int enum_type_dissect_from_buffer(
 
     for (values = type->child; values; values = values->next) {
         if (value == values->init_value) {
+            values->parent = type;
             values->type_dissect_from_buffer(
                 values, ui_set_signal_text_cb, user_data, buffer, offset, parent_offset,
                 type->name == NULL ? indent: indent+4);
diff --git a/common/utils/itti_analyzer/libparser/enum_value_type.c b/common/utils/itti_analyzer/libparser/enum_value_type.c
index 752d9654dc..bb560ae983 100644
--- a/common/utils/itti_analyzer/libparser/enum_value_type.c
+++ b/common/utils/itti_analyzer/libparser/enum_value_type.c
@@ -6,10 +6,13 @@
 #include "enum_value_type.h"
 #include "ui_interface.h"
 
+uint32_t last_enum_value;
+
 int enum_value_dissect_from_buffer(
     struct types_s *type, ui_set_signal_text_cb_t ui_set_signal_text_cb, gpointer user_data,
     buffer_t *buffer, uint32_t offset, uint32_t parent_offset, int indent)
 {
+    struct types_s *type_parent = NULL;
     uint32_t value = 0;
 
     DISPLAY_PARSE_INFO("enum_value", type->name, offset, parent_offset);
@@ -19,6 +22,24 @@ int enum_value_dissect_from_buffer(
         int length = 0;
         char cbuf[50 + strlen(type->name)];
 
+        /* Search for enum variable name and check if it is used in association with a union type */
+        {
+            if (type->parent != NULL) {
+                /* Ignore ENUMERATION and TYPEDEF parents */
+                for (type_parent = type->parent; (type_parent != NULL) && ((type_parent->type == TYPE_ENUMERATION) || (type_parent->type == TYPE_TYPEDEF));
+                        type_parent = type_parent->parent) {
+                }
+            }
+            if ((type_parent != NULL) && (type_parent->name != NULL) && (strcmp(type_parent->name, "present") == 0))
+            {
+                /* ASN1 union, keep the "present" member */
+                last_enum_value = value;
+            }
+            else
+            {
+                last_enum_value = 0;
+            }
+        }
         sprintf(cbuf, "(0x%08x)  %s;\n", value, type->name);
         length = strlen(cbuf);
 
diff --git a/common/utils/itti_analyzer/libparser/enum_value_type.h b/common/utils/itti_analyzer/libparser/enum_value_type.h
index 0bfb7d821b..6db1152482 100644
--- a/common/utils/itti_analyzer/libparser/enum_value_type.h
+++ b/common/utils/itti_analyzer/libparser/enum_value_type.h
@@ -3,6 +3,8 @@
 #ifndef ENUM_VALUE_TYPE_H_
 #define ENUM_VALUE_TYPE_H_
 
+extern uint32_t last_enum_value;
+
 int enum_value_dissect_from_buffer(
     struct types_s *type, ui_set_signal_text_cb_t ui_set_signal_text_cb, gpointer user_data,
     buffer_t *buffer, uint32_t offset, uint32_t parent_offset, int indent);
diff --git a/common/utils/itti_analyzer/libparser/field_type.c b/common/utils/itti_analyzer/libparser/field_type.c
index 348c26a5fe..225a75c8a2 100644
--- a/common/utils/itti_analyzer/libparser/field_type.c
+++ b/common/utils/itti_analyzer/libparser/field_type.c
@@ -24,55 +24,67 @@ int field_dissect_from_buffer(
     CHECK_FCT(buffer_has_enouch_data(buffer, parent_offset + offset, type->size / 8));
 
     if (type->bits == -1) {
-        if (type->child != NULL) {
-            /* Ignore TYPEDEF children */
-            for (type_child = type->child; type_child != NULL && type_child->type == TYPE_TYPEDEF; type_child =
-                    type_child->child) {
-            }
-
-            if (type_child->type == TYPE_ARRAY) {
-                struct types_s *type_array_child;
+        if ((type->name != NULL) && (strcmp(type->name, "_asn_ctx") == 0)) {
+           /* Hide ASN1 asn_struct_ctx_t struct that hold context for parsing across buffer boundaries */
+           /*
+           INDENTED_STRING(cbuf, indent, sprintf(cbuf, ".asn_ctx ...\n"));
+           length = strlen (cbuf);
 
+           ui_set_signal_text_cb(user_data, cbuf, length);
+           */
+        }
+        else {
+            if (type->child != NULL) {
                 /* Ignore TYPEDEF children */
-                for (type_array_child = type_child->child;
-                        type_array_child != NULL && type_array_child->type == TYPE_TYPEDEF; type_array_child =
-                                type_array_child->child) {
+                for (type_child = type->child; type_child != NULL && type_child->type == TYPE_TYPEDEF; type_child =
+                        type_child->child) {
                 }
 
-                sprintf (array_info, "[%d]", type_child->size / type_array_child->size);
+                if (type_child->type == TYPE_ARRAY) {
+                    struct types_s *type_array_child;
+
+                    /* Ignore TYPEDEF children */
+                    for (type_array_child = type_child->child;
+                            type_array_child != NULL && type_array_child->type == TYPE_TYPEDEF; type_array_child =
+                                    type_array_child->child) {
+                    }
+
+                    sprintf (array_info, "[%d]", type_child->size / type_array_child->size);
+                }
+                else {
+                    array_info[0] = '\0';
+                }
+
+                DISPLAY_TYPE("Fld");
+                INDENTED_STRING(cbuf, indent, sprintf(cbuf, ".%s%s = ", type->name ? type->name : "Field", array_info));
+                length = strlen (cbuf);
+
+                ui_set_signal_text_cb(user_data, cbuf, length);
+
+                indent_child = indent;
+                if (type_child->type == TYPE_ARRAY || type_child->type == TYPE_STRUCT || type_child->type == TYPE_UNION) {
+                    DISPLAY_BRACE(ui_set_signal_text_cb(user_data, "{", 1);)
+                    ui_set_signal_text_cb(user_data, "\n", 1);
+                    indent_child += 4;
+                }
+                if (type_child->type == TYPE_FUNDAMENTAL || type_child->type == TYPE_POINTER) {
+                    indent_child = 0;
+                }
+
+                type->child->parent = type;
+                CHECK_FCT(type->child->type_dissect_from_buffer(
+                        type->child, ui_set_signal_text_cb, user_data, buffer,
+                        parent_offset, offset + type->offset, indent_child));
+
+                DISPLAY_BRACE(
+                        if (type_child->type == TYPE_ARRAY || type_child->type == TYPE_STRUCT || type_child->type == TYPE_UNION) {
+                            DISPLAY_TYPE("Fld");
+                            INDENTED_STRING(cbuf, indent, sprintf(cbuf, "};\n"));
+                            length = strlen (cbuf);
+
+                            ui_set_signal_text_cb(user_data, cbuf, length);
+                        });
             }
-            else {
-                array_info[0] = '\0';
-            }
-
-            DISPLAY_TYPE("Fld");
-            INDENTED_STRING(cbuf, indent, sprintf(cbuf, ".%s%s = ", type->name ? type->name : "Field", array_info));
-            length = strlen (cbuf);
-
-            ui_set_signal_text_cb(user_data, cbuf, length);
-
-            indent_child = indent;
-            if (type_child->type == TYPE_ARRAY || type_child->type == TYPE_STRUCT || type_child->type == TYPE_UNION) {
-                DISPLAY_BRACE(ui_set_signal_text_cb(user_data, "{", 1);)
-                ui_set_signal_text_cb(user_data, "\n", 1);
-                indent_child += 4;
-            }
-            if (type_child->type == TYPE_FUNDAMENTAL || type_child->type == TYPE_POINTER) {
-                indent_child = 0;
-            }
-
-            CHECK_FCT(type->child->type_dissect_from_buffer(
-                    type->child, ui_set_signal_text_cb, user_data, buffer,
-                    parent_offset, offset + type->offset, indent_child));
-
-            DISPLAY_BRACE(
-                    if (type_child->type == TYPE_ARRAY || type_child->type == TYPE_STRUCT || type_child->type == TYPE_UNION) {
-                        DISPLAY_TYPE("Fld");
-                        INDENTED_STRING(cbuf, indent, sprintf(cbuf, "};\n"));
-                        length = strlen (cbuf);
-
-                        ui_set_signal_text_cb(user_data, cbuf, length);
-                    });
         }
     }
     else {
diff --git a/common/utils/itti_analyzer/libparser/typedef_type.c b/common/utils/itti_analyzer/libparser/typedef_type.c
index ce5f0f9313..193e7449fb 100644
--- a/common/utils/itti_analyzer/libparser/typedef_type.c
+++ b/common/utils/itti_analyzer/libparser/typedef_type.c
@@ -14,6 +14,7 @@ int typedef_dissect_from_buffer(
 
     /* Simply call next_type */
     if (type->child != NULL) {
+        type->child->parent = type;
         type->child->type_dissect_from_buffer(
             type->child, ui_set_signal_text_cb, user_data, buffer, offset, parent_offset, indent);
     }
diff --git a/common/utils/itti_analyzer/libparser/union_type.c b/common/utils/itti_analyzer/libparser/union_type.c
index 6976bf1bed..a37db03ad0 100644
--- a/common/utils/itti_analyzer/libparser/union_type.c
+++ b/common/utils/itti_analyzer/libparser/union_type.c
@@ -5,6 +5,7 @@
 
 #include "rc.h"
 
+#include "enum_value_type.h"
 #include "union_type.h"
 #include "../libresolver/locate_root.h"
 #include "ui_interface.h"
@@ -34,6 +35,7 @@ int union_dissect_from_buffer(
 {
     int length = 0;
     char cbuf[200];
+    int union_child = 0;
 
     DISPLAY_PARSE_INFO("union", type->name, offset, parent_offset);
 
@@ -45,6 +47,21 @@ int union_dissect_from_buffer(
 //         INDENTED(stdout, indent,   fprintf(stdout, "<%s>\n", type->name));
         DISPLAY_TYPE("Uni");
         INDENTED_STRING(cbuf, indent, sprintf(cbuf, "%s {\n", type->name));
+
+        if (type->parent != NULL)
+        {
+            if ((type->parent->name != NULL) && (strcmp(type->parent->name, "choice") == 0))
+            {
+                /* ASN1 union */
+
+                if ((last_enum_value > 0) && (last_enum_value <= type->nb_members))
+                {
+                    union_child = last_enum_value - 1;
+
+                    g_debug("ASN1 union \"%s\' detected, use member %d", type->name, union_child);
+                }
+            }
+        }
     }
 
     length = strlen (cbuf);
@@ -52,9 +69,9 @@ int union_dissect_from_buffer(
     ui_set_signal_text_cb(user_data, cbuf, length);
 
     /* Only dissect the first field present in unions */
-    if (type->members_child[0] != NULL)
-        type->members_child[0]->type_dissect_from_buffer(
-            type->members_child[0], ui_set_signal_text_cb, user_data, buffer,
+    if (type->members_child[union_child] != NULL)
+        type->members_child[union_child]->type_dissect_from_buffer(
+            type->members_child[union_child], ui_set_signal_text_cb, user_data, buffer,
             offset, parent_offset, type->name == NULL ? indent : indent + 4);
 
     if (type->name) {