diff --git a/openbsc/src/gprs/sgsn_main.c b/openbsc/src/gprs/sgsn_main.c
new file mode 100644
index 0000000..15f760d
--- /dev/null
+++ b/openbsc/src/gprs/sgsn_main.c
@@ -0,0 +1,143 @@
+/* GPRS SGSN Implementation */
+
+/* (C) 2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010 by On Waves
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <errno.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <osmocore/talloc.h>
+#include <osmocore/select.h>
+
+#include <openbsc/signal.h>
+#include <openbsc/debug.h>
+#include <openbsc/telnet_interface.h>
+#include <openbsc/vty.h>
+#include <openbsc/sgsn.h>
+#include <openbsc/gprs_ns.h>
+#include <openbsc/gprs_bssgp.h>
+
+#include "../../bscconfig.h"
+
+/* this is here for the vty... it will never be called */
+void subscr_put() { abort(); }
+
+#define _GNU_SOURCE
+#include <getopt.h>
+
+void *tall_bsc_ctx;
+
+struct gprs_ns_inst *sgsn_nsi;
+
+const char *openbsc_version = "Osmocom NSIP Proxy " PACKAGE_VERSION;
+const char *openbsc_copyright =
+	"Copyright (C) 2010 Harald Welte and On-Waves\n"
+	"Contributions by Daniel Willmann, Jan Lübbe, Stefan Schmidt\n"
+	"Dieter Spaar, Andreas Eversberg, Holger Freyther\n\n"
+	"License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>\n"
+	"This is free software: you are free to change and redistribute it.\n"
+	"There is NO WARRANTY, to the extent permitted by law.\n";
+
+static char *config_file = "osmo_sgsn.cfg";
+static struct sgsn_config sgcfg;
+
+/* call-back function for the NS protocol */
+static int sgsn_ns_cb(enum gprs_ns_evt event, struct gprs_nsvc *nsvc,
+		      struct msgb *msg, u_int16_t bvci)
+{
+	int rc = 0;
+
+	switch (event) {
+	case GPRS_NS_EVT_UNIT_DATA:
+		/* hand the message into the BSSGP implementation */
+		rc = gprs_bssgp_rcvmsg(msg);
+		break;
+	default:
+		LOGP(DGPRS, LOGL_ERROR, "SGSN: Unknown event %u from NS\n", event);
+		if (msg)
+			talloc_free(msg);
+		rc = -EIO;
+		break;
+	}
+	return rc;
+}
+
+/* NSI that BSSGP uses when transmitting on NS */
+extern struct gprs_ns_inst *bssgp_nsi;
+
+int main(int argc, char **argv)
+{
+	struct gsm_network dummy_network;
+	struct log_target *stderr_target;
+	struct sockaddr_in sin;
+	int rc;
+
+	tall_bsc_ctx = talloc_named_const(NULL, 0, "osmo_sgsn");
+
+	log_init(&log_info);
+	stderr_target = log_target_create_stderr();
+	log_add_target(stderr_target);
+	log_set_all_filter(stderr_target, 1);
+
+	telnet_init(&dummy_network, 4245);
+	rc = sgsn_parse_config(config_file, &sgcfg);
+	if (rc < 0) {
+		LOGP(DGPRS, LOGL_FATAL, "Cannot parse config file\n");
+		exit(2);
+	}
+
+	sgsn_nsi = gprs_ns_instantiate(&sgsn_ns_cb);
+	if (!sgsn_nsi) {
+		LOGP(DGPRS, LOGL_ERROR, "Unable to instantiate NS\n");
+		exit(1);
+	}
+	bssgp_nsi = sgcfg.nsi = sgsn_nsi;
+	nsip_listen(sgsn_nsi, sgcfg.nsip_listen_port);
+
+	while (1) {
+		rc = bsc_select_main(0);
+		if (rc < 0)
+			exit(3);
+	}
+
+	exit(0);
+}
+
+struct gsm_network;
+int bsc_vty_init(struct gsm_network *dummy)
+{
+	cmd_init(1);
+	vty_init();
+
+	openbsc_vty_add_cmds();
+        sgsn_vty_init();
+	return 0;
+}
+