diff --git a/library/SMPP_CodecPort.ttcn b/library/SMPP_CodecPort.ttcn
new file mode 100644
index 0000000..0ac81ae
--- /dev/null
+++ b/library/SMPP_CodecPort.ttcn
@@ -0,0 +1,65 @@
+module SMPP_CodecPort {
+
+/* Simple SMPP Codec Port, translating between raw TCP octetstring payload
+ * towards the IPL4asp port provider, and SMPP primitives
+ * which carry the decoded SMPP data types as payload.
+ *
+ * (C) 2018 by Harald Welte <laforge@gnumonks.org>
+ * All rights reserved.
+ *
+ * Released under the terms of GNU General Public License, Version 2 or
+ * (at your option) any later version.
+ */
+
+
+import from IPL4asp_PortType all;
+import from IPL4asp_Types all;
+import from SMPP_Types all;
+
+type record SMPP_RecvFrom {
+	ConnectionId	connId,
+	SMPP_PDU	msg
+}
+
+type record SMPP_Send {
+	ConnectionId	connId,
+	SMPP_PDU	msg
+}
+
+template (value) SMPP_Send ts_SMPP_Send(ConnectionId conn_id, template (value) SMPP_PDU msg) := {
+	connId := conn_id,
+	msg := msg
+}
+
+template SMPP_RecvFrom tr_SMPP_Recv(template ConnectionId conn_id, template SMPP_PDU msg) := {
+	connId := conn_id,
+	msg := msg
+}
+
+private function IPL4_to_SMPP_RecvFrom(in ASP_RecvFrom pin, out SMPP_RecvFrom pout) {
+	var integer rc;
+	pout.connId := pin.connId;
+	rc := f_decode_SMPP(pin.msg, pout.msg);
+} with { extension "prototype(fast)" }
+
+private function SMPP_to_IPL4_Send(in SMPP_Send pin, out ASP_Send pout) {
+	pout.connId := pin.connId;
+	pout.proto := { tcp := {} };
+	f_encode_SMPP(pin.msg, pout.msg);
+} with { extension "prototype(fast)" }
+
+type port SMPP_CODEC_PT message {
+	out	SMPP_Send;
+	in	SMPP_RecvFrom,
+		ASP_ConnId_ReadyToRelease,
+		ASP_Event;
+} with { extension "user IPL4asp_PT
+	out(SMPP_Send -> ASP_Send: function(SMPP_to_IPL4_Send))
+	in(ASP_RecvFrom -> SMPP_RecvFrom: function(IPL4_to_SMPP_RecvFrom);
+	   ASP_ConnId_ReadyToRelease -> ASP_ConnId_ReadyToRelease: simple;
+	   ASP_Event -> ASP_Event: simple)"
+}
+
+
+
+}