diff --git a/asterisk/IMS_ConnectionHandler.ttcn b/asterisk/IMS_ConnectionHandler.ttcn
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+/* Component implementing a IMS server towards Asterisk's IMS UE
+ * (C) 2024 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Pau Espin Pedrol <pespin@sysmocom.de>
+ * All rights reserved.
+ *
+ * Released under the terms of GNU General Public License, Version 2 or
+ * (at your option) any later version.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+module IMS_ConnectionHandler {
+
+import from TCCOpenSecurity_Functions all;
+import from General_Types all;
+import from Osmocom_Types all;
+import from Native_Functions all;
+import from Misc_Helpers all;
+
+import from SDP_Types all;
+import from SDP_Templates all;
+
+import from SIP_Emulation all;
+import from SIPmsg_Types all;
+import from SIP_Templates all;
+
+type port IMSCoord_PT message
+{
+	inout charstring;
+} with { extension "internal" };
+
+const charstring IMS_COORD_CMD_REGISTERED := "COORD_CMD_REGISTERED";
+
+type component IMS_ConnHdlr extends SIP_ConnHdlr {
+	var charstring g_name;
+	var IMS_ConnHdlrPars g_pars;
+	timer g_Tguard;
+	var PDU_SIP_Request g_rx_sip_req;
+	var PDU_SIP_Response g_rx_sip_resp;
+
+	port IMSCoord_PT COORD;
+}
+type record of IMS_ConnHdlr IMS_ConnHdlrList;
+
+type record IMS_ConnHdlrPars {
+	float t_guard,
+	charstring remote_sip_host,
+	uint16_t remote_sip_port,
+	charstring user,
+	charstring display_name,
+	charstring password,
+	SipUrl registrar_sip_req_uri,
+	SipAddr registrar_sip_record,
+	CallidString registrar_sip_call_id,
+	integer registrar_sip_seq_nr,
+	Via local_via,
+	SipUrl local_sip_url_ext,
+	SipAddr local_sip_record,
+	Contact local_contact,
+	IMS_CallPars cp optional
+}
+type record of IMS_ConnHdlrPars IMS_ConnHdlrParsList;
+
+type record IMS_CallParsMT {
+	/* Whether to wait for COORD.receive(COORD_CMD_PICKUP) before accepting the call. */
+	boolean wait_coord_cmd_pickup,
+	/* Whether to expect CANCEL instead of ACK as answer to our OK */
+	boolean exp_cancel
+}
+
+type record IMS_CallPars {
+	SipAddr calling optional,
+	SipAddr called optional,
+
+	SipAddr from_addr optional,
+	SipAddr to_addr optional,
+
+	CallidString sip_call_id,
+	integer sip_seq_nr,
+	charstring sip_body optional,
+
+	charstring local_rtp_addr,
+	uint16_t local_rtp_port,
+
+	SDP_Message peer_sdp optional,
+	IMS_CallParsMT mt
+}
+
+}