diff --git a/exports/nss_dynamic_interface.h b/exports/nss_dynamic_interface.h
index ca41ef2..3aa7803 100644
--- a/exports/nss_dynamic_interface.h
+++ b/exports/nss_dynamic_interface.h
@@ -49,7 +49,8 @@
 	NSS_DYNAMIC_INTERFACE_TYPE_PORTID,
 	NSS_DYNAMIC_INTERFACE_TYPE_DTLS,
 	NSS_DYNAMIC_INTERFACE_TYPE_MAP_T,
-	NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL,
+	NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_INNER,
+	NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_OUTER,
 	NSS_DYNAMIC_INTERFACE_TYPE_BRIDGE,
 	NSS_DYNAMIC_INTERFACE_TYPE_VLAN,
 	NSS_DYNAMIC_INTERFACE_TYPE_GRE,
diff --git a/exports/nss_gre_tunnel.h b/exports/nss_gre_tunnel.h
index 0bb30fa..0b54244 100644
--- a/exports/nss_gre_tunnel.h
+++ b/exports/nss_gre_tunnel.h
@@ -88,6 +88,8 @@
 	NSS_GRE_TUNNEL_ERR_ENCRYPT_IDX_INVALID = 7,
 	NSS_GRE_TUNNEL_ERR_NOMEM = 8,
 	NSS_GRE_TUNNEL_ERR_PROTO_TEB_INVALID = 9,
+	NSS_GRE_TUNNEL_ERR_SIBLING_IF = 10,
+	NSS_GRE_TUNNEL_ERR_CRYPTO_NODE_ID = 11,
 	NSS_GRE_TUNNEL_ERR_MAX,
 };
 
@@ -103,12 +105,14 @@
 	uint32_t dest_ip[4];		/**< Destination IPv4 or IPv6 address. */
 	uint16_t src_port;		/**< GRE plus UDP only for the source. */
 	uint16_t dest_port;		/**< GRE plus UDP only for the destination. */
+	uint32_t crypto_node_id;	/**< Cryto node identifier. */
 	uint32_t crypto_idx_encrypt;	/**< Crypto index for encryption. */
 	uint32_t crypto_idx_decrypt;	/**< Crypto index for decryption. */
 	uint32_t word0;			/**< Word0 header. */
 	uint8_t iv_val[16];		/**< Initialization vector value. */
 	uint8_t ttl;			/**< Time-to-live value of the IP header. */
 	uint8_t mh_version;		/**< Meta header version */
+	uint32_t sibling_if;		/**< Sibling interface number. */
 };
 
 /**
diff --git a/nss_gre_tunnel.c b/nss_gre_tunnel.c
index cdff637..c6ff894 100644
--- a/nss_gre_tunnel.c
+++ b/nss_gre_tunnel.c
@@ -42,13 +42,12 @@
  */
 static bool nss_gre_tunnel_verify_if_num(uint32_t if_num)
 {
-	if (nss_is_dynamic_interface(if_num) == false)
-		return false;
+	uint32_t type = nss_dynamic_interface_get_type(nss_gre_tunnel_get_ctx(), if_num);
+	if ((type == NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_INNER) || (type == NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_OUTER)) {
+		return true;
+	}
 
-	if (nss_dynamic_interface_get_type(nss_gre_tunnel_get_ctx(), if_num) != NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL)
-		return false;
-
-	return true;
+	return false;
 }
 
 /*
diff --git a/nss_hal/nss_hal.c b/nss_hal/nss_hal.c
index d0959e9..6655d42 100644
--- a/nss_hal/nss_hal.c
+++ b/nss_hal/nss_hal.c
@@ -457,7 +457,8 @@
 
 	if (npd->gre_tunnel_enabled == NSS_FEATURE_ENABLED) {
 		nss_top->gre_tunnel_handler_id = nss_dev->id;
-		nss_top->dynamic_interface_table[NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL] = nss_dev->id;
+		nss_top->dynamic_interface_table[NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_INNER] = nss_dev->id;
+		nss_top->dynamic_interface_table[NSS_DYNAMIC_INTERFACE_TYPE_GRE_TUNNEL_OUTER] = nss_dev->id;
 	}
 
 	if (npd->portid_enabled == NSS_FEATURE_ENABLED) {