diff --git a/src/abis_nm.c b/src/abis_nm.c
new file mode 100644
index 0000000..c873b95
--- /dev/null
+++ b/src/abis_nm.c
@@ -0,0 +1,419 @@
+/* GSM Network Management (OML) messages on the A-bis interface 
+ * 3GPP TS 12.21 version 8.0.0 Release 1999 / ETSI TS 100 623 V8.0.0 */
+
+/* (C) 2008 by Harald Welte <laforge@gnumonks.org>
+ * 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 <errno.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include "gsm_data.h"
+#include "debug.h"
+#include "msgb.h"
+#include "abis_nm.h"
+
+#define OM_ALLOC_SIZE	1024
+
+/* unidirectional messages from BTS to BSC */
+static const enum abis_nm_msgtype reports[] = {
+	NM_MT_SW_ACTIVATED_REP,
+	NM_MT_TEST_REP,
+	NM_MT_STATECHG_EVENT_REP,
+	NM_MT_FAILURE_EVENT_REP,
+};
+
+/* messages without ACK/NACK */
+static const enum abis_nm_msgtype no_ack_nack[] = {
+	NM_MT_MEAS_RES_REQ,
+	NM_MT_STOP_MEAS,
+	NM_MT_START_MEAS,
+};
+
+/* Attributes that the BSC can set, not only get, according to Section 9.4 */
+static const enum abis_nm_attr nm_att_settable[] = {
+	NM_ATT_ADD_INFO,
+	NM_ATT_ADD_TEXT,
+	NM_ATT_DEST,
+	NM_ATT_EVENT_TYPE,
+	NM_ATT_FILE_DATA,
+	NM_ATT_GET_ARI,
+	NM_ATT_HW_CONF_CHG,
+	NM_ATT_LIST_REQ_ATTR,
+	NM_ATT_MDROP_LINK,
+	NM_ATT_MDROP_NEXT,
+	NM_ATT_NACK_CAUSES,
+	NM_ATT_OUTST_ALARM,
+	NM_ATT_PHYS_CONF,
+	NM_ATT_PROB_CAUSE,
+	NM_ATT_RAD_SUBC,
+	NM_ATT_SOURCE,
+	NM_ATT_SPEC_PROB,
+	NM_ATT_START_TIME,
+	NM_ATT_TEST_DUR,
+	NM_ATT_TEST_NO,
+	NM_ATT_TEST_REPORT,
+	NM_ATT_WINDOW_SIZE,
+	NM_ATT_SEVERITY,
+	NM_ATT_MEAS_RES,
+	NM_ATT_MEAS_TYPE,
+};
+
+static int is_in_arr(enum abis_nm_msgtype mt, const enum abis_nm_msgtype *arr, int size)
+{
+	int i;
+
+	for (i = 0; i < size; i++) {
+		if (arr[i] == mt)
+			return 1;
+	}
+
+	return 0;
+}
+
+/* is this msgtype the usual ACK/NACK type ? */
+static int is_ack_nack(enum abis_nm_msgtype mt)
+{
+	return !is_in_arr(mt, no_ack_nack, ARRAY_SIZE(no_ack_nack));
+}
+
+/* is this msgtype a report ? */
+static int is_report(enum abis_nm_msgtype mt)
+{
+	return is_in_arr(mt, reports, ARRA_YSIZE(reports));
+}
+
+#define MT_ACK(x)	(x+1)
+#define MT_NACK(x)	(x+2)
+
+static void fill_om_hdr(struct abis_om_hdr *oh, u_int8_t len)
+{
+	oh->mdisc = ABIS_OM_MDISC_FOM;
+	oh->placement = ABIS_OM_PLACEMENT_ONLY;
+	oh->sequence = 0;
+	oh->length = len;
+}
+
+static void fill_om_fom_hdr(struct abis_om_hdr *oh, u_int8_t len,
+			    u_int8_t msg_type, u_int8_t obj_class,
+			    u_int8_t bts_nr, u_int8_t trx_nr, u_int8_t ts_nr)
+{
+	struct abis_om_fom_hdr *foh =
+			(struct abis_om_fom_hdr *) oh->data;
+
+	fill_om_hdr(oh, len);
+	foh->msg_type = msg_type;
+	foh->obj_class = obj_class;
+	foh->obj_inst.bts_nr = bts_nr;
+	foh->obj_inst.trx_nr = trx_nr;
+	foh->obj_inst.ts_nr = ts_nr;
+}
+
+/* Send a OML NM Message from BSC to BTS */
+int abis_nm_sendmsg(struct gsm_bts *bts, struct msgb *msg)
+{
+	/* FIXME */
+}
+
+/* Receive a OML NM Message from BTS */
+static int abis_nm_rcvmsg(struct msgb *mb)
+{
+	struct abis_om_fom_hdr *foh = msgb_l3(mb);
+	u_int8_t mt = foh->msg_type;
+
+	/* check for unsolicited message */
+	if (is_report(mt)) {
+		nmh->cfg->report_cb(mb, foh);
+		return 0;
+	}
+
+	/* check if last message is to be acked */
+	if (is_ack_nack(nmh->last_msgtype)) {
+		if (mt == MT_ACK(nmh->last_msgtype)) {
+			fprintf(stderr, "received ACK (0x%x)\n",
+				foh->msg_type);
+			/* we got our ACK, continue sending the next msg */
+		} else if (mt == MT_NACK(nmh->last_msgtype)) {
+			/* we got a NACK, signal this to the caller */
+			fprintf(stderr, "received NACK (0x%x)\n",
+				foh->msg_type);
+			/* FIXME: somehow signal this to the caller */
+		} else {
+			/* really strange things happen */
+			return -EINVAL;
+		}
+	}
+}
+
+/* High-Level API */
+/* Entry-point where L2 OML from BTS enters the NM code */
+int abis_nm_rx(struct msgb *msg)
+{
+	int rc;
+	struct abis_om_hdr *oh = msgb_l2(msg);
+	unsigned int l2_len = msg->tail - msg_l2(msg);
+
+	/* Various consistency checks */
+	if (oh->placement != ABIS_OM_PLACEMENT_ONLY) {
+		fprintf(stderr, "ABIS OML placement 0x%x not supported\n",
+			oh->placement);
+		return -EINVAL;
+	}
+	if (oh->sequence != 0) {
+		fprintf(stderr, "ABIS OML sequence 0x%x != 0x00\n",
+			oh->sequence);
+		return -EINVAL;
+	}
+	if (oh->length + sizeof(*oh) > l2_len) {
+		fprintf(stderr, "ABIS OML truncated message (%u > %u)\n",
+			oh->length + sizeof(*oh), l2_len);
+		return -EINVAL;
+	}
+	if (oh->length + sizeof(*oh) < l2_len)
+		fprintf(stderr, "ABIS OML message with extra trailer?!?\n");
+
+	msg->l3_off = ((unsigned char *)oh + sizeof(*oh)) - msg->head;
+
+	switch (oh->mdisc) {
+	case ABIS_OM_MDISC_FOM:
+		rc = abis_nm_rcvmsg(msg);
+		break;
+	case ABIS_OM_MDISC_MMI:
+	case ABIS_OM_MDISC_TRAU:
+	case ABIS_OM_MDISC_MANUF:
+	default:
+		fprintf(stderr, "unknown ABIS OML message discriminator 0x%x\n",
+			oh->mdisc);
+		return -EINVAL;
+	}
+
+	return rc;
+}
+
+#if 0
+/* initialized all resources */
+struct abis_nm_h *abis_nm_init(struct abis_nm_cfg *cfg)
+{
+	struct abis_nm_h *nmh;
+
+	nmh = malloc(sizeof(*nmh));
+	if (!nmh)
+		return NULL;
+
+	nmh->cfg = cfg;
+
+	return nmh;
+}
+
+/* free all resources */
+void abis_nm_fini(struct abis_nm_h *nmh)
+{
+	free(nmh);
+}
+#endif
+
+/* Here we are trying to define a high-level API that can be used by
+ * the actual BSC implementation.  However, the architecture is currently
+ * still under design.  Ideally the calls to this API would be synchronous,
+ * while the underlying stack behind the APi runs in a traditional select
+ * based state machine.
+ */
+
+/* 6.2 Software Load: FIXME */
+
+
+#if 0
+struct abis_nm_sw {
+	/* this will become part of the SW LOAD INITIATE */
+	u_int8_t obj_class;
+	u_int8_t obj_instance[3];
+	u_int8_t sw_description[255];
+	u_int16_t window_size;
+	/* the actual data that is to be sent subsequently */
+	unsigned char *sw;
+	unsigned int sw_len;
+};
+
+/* Load the specified software into the BTS */
+int abis_nm_sw_load(struct abis_nm_h *h, struct abis_nm_sw *sw);
+{
+	/* FIXME: Implementation */
+}
+
+/* Activate the specified software into the BTS */
+int abis_nm_sw_activate(struct abis_nm_h *h)
+{
+
+}
+#endif
+
+static fill_nm_channel(struct abis_nm_channel *ch, u_int8_t bts_port,
+		       u_int8_t ts_nr, u_int8_t subslot_nr)
+{
+	ch->attrib = NM_ATT_CHANNEL;
+	ch->bts_port = bts_port;
+	ch->timeslot = ts_nr;
+	ch->subslot = subslot_nr;	
+}
+
+int abis_nm_establish_tei(struct gsm_bts *bts, u_int8_t trx_nr,
+			  u_int8_t e1_port, u_int8_t e1_timeslot, u_int8_t e1_subslot,
+			  u_int8_t tei)
+{
+	struct abis_om_hdr *oh;
+	struct abis_nm_channel *ch;
+	u_int8_t *tei_attr;
+	u_int8_t len = 2 + sizeof(*ch);
+	struct mgsb *msg = msgb_alloc(OM_ALLOC_SIZE);
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, ABIS_OM_FOM_HDR_SIZE);
+	fill_om_fom_hdr(oh, len, NM_MT_ESTABLISH_TEI, NM_OC_RADIO_CARRIER,
+			bts->bts_nr, trx_nr, 0xff);
+	
+	msgb_tv_put(msgb, NM_ATT_TEI, tei);
+
+	ch = (struct abis_nm_channel *) msgb_put(msg, sizeof(*ch));
+	fill_nm_channel(ch, e1_port, e1_timeslot, e1_subslot);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+/* connect signalling of one (BTS,TRX) to a particular timeslot on the E1 */
+int abis_nm_conn_terr_sign(struct gsm_bts_trx *trx,
+			   u_int8_t e1_port, u_int8_t e1_timeslot, u_int8_t e1_subslot)
+{
+	struct gsm_bts *bts = ts->trx->bts;
+	struct abis_om_hdr *oh;
+	struct abis_nm_channel *ch;
+	struct mgsb *msg = msgb_alloc(OM_ALLOC_SIZE);
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, ABIS_OM_FOM_HDR_SIZE);
+	fill_om_fom_hdr(oh, sizeof(*ch), NM_MT_CONN_TERR_SIGN,
+			NM_OC_RADIO_CARRIER, bts->bts_nr, trx->nr, 0xff);
+	
+	ch = (struct abis_nm_channel *) msgb_put(msg, sizeof(*ch));
+	fill_nm_channel(ch, e1_port, e1_timeslot, e1_subslot);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+#if 0
+int abis_nm_disc_terr_sign(struct abis_nm_h *h, struct abis_om_obj_inst *inst,
+			   struct abis_nm_abis_channel *chan)
+{
+}
+#endif
+
+int abis_nm_conn_terr_traf(struct gsm_bts_trx_ts *ts,
+			   u_int8_t e1_port, u_int8_t e1_timeslot,
+			   u_int8_t e1_subslot)
+{
+	struct gsm_bts *bts = ts->trx->bts;
+	struct abis_om_hdr *oh;
+	struct abis_nm_channel *ch;
+	struct msgb *msg = msgb_alloc(OM_ALLOC_SIZE);
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, ABIS_OM_FOM_HDR_SIZE);
+	fill_om_fom_hdr(oh, sizeof(*ch), NM_MT_CONN_TERR_TRAF,
+			NM_OC_BASEB_TRANSC, bts->bts_nr, ts->trx->nr, ts->nr);
+
+	ch = (struct abis_nm_channel *) msgb_put(msg, sizeof(*ch));
+	fill_nm_channel(ch, e1_port, e1_timeslot, e1_subslot);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+#if 0
+int abis_nm_disc_terr_traf(struct abis_nm_h *h, struct abis_om_obj_inst *inst,
+			   struct abis_nm_abis_channel *chan,
+			   u_int8_t subchan)
+{
+}
+#endif
+
+int abis_nm_set_channel_attr(struct gsm_bts_trx_ts *ts, u_int8_t chan_comb)
+{
+	struct gsm_bts *bts = ts->trx->bts;
+	struct abis_om_hdr *oh;
+	u_int8_t arfcn = htons(ts->trx->arfcn);
+	u_int8_t zero = 0x00;
+	struct msgb *msg = msgb_alloc(OM_ALLOC_SIZE);
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, ABIS_OM_FOM_HDR_SIZE);
+	fill_om_fom_hdr(oh, sizeof(*ch), NM_MT_SET_CHAN_ATTR,
+			NM_OC_BASEB_TRANSC, bts->bts_nr,
+			ts->trx->nr, ts->nr);
+	/* FIXME: don't send ARFCN list, hopping sequence, mAIO, ...*/
+	msgb_tlv16_put(msg, NM_ATT_ARFCN_LIST, 1, &arfcn);
+	msgb_tv_put(msg, NM_ATT_CHAN_COMB, chan_comb);
+	msgb_tv_put(msg, NM_ATT_HSN, 0x00);
+	msgb_tv_put(msg, NM_ATT_MAIO, 0x00);
+	msgb_tv_put(msg, NM_ATT_TSC, 0x07);	/* training sequence */
+	msgb_tlv_put(msg, 0x59, 1, &zero);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+int abis_nm_raw_msg(struct gsm_bts *bts, int len, u_int8_t *msg)
+{
+	struct msgb *msg = msgb_alloc(OM_ALLOC_SIZE);
+	u_int8_t *data;
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, sizeof(*oh));
+	fill_om_hdr(oh, len);
+	data = msgb_put(msg, len);
+	memcpy(msgb->data, msg, len);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+/* Siemens specific commands */
+static int __simple_cmd(struct gsm_bts *bts, u_int8_t msg_type)
+{
+	struct abis_om_hdr *oh;
+	struct msg = msgb_alloc(OM_ALLOC_SIZE);
+
+	oh = (struct abis_om_hdr *) msgb_put(msg, ABIS_OM_FOM_HDR_SIZE);
+	fill_om_fom_hdr(oh, sizeof(*ch), msg_type, NM_OC_SITE_MANAGER,
+			0xff, 0xff, 0xff);
+
+	return abis_nm_sendmsg(bts, msg);
+}
+
+int abis_nm_event_reports(struct gsm_bts *bts, int on)
+{
+	if (on == 0)
+		return __simple_cmd(bts, 0x63);
+	else
+		return __simple_cmd(bts, 0x66);
+}
+
+int abis_nm_reset_resource(struct gsm_bts *bts)
+{
+	return __simple_cmd(bts, 0x74);
+}
+
+int abis_nm_db_transaction(struct gsm_bts *bts, int begin)
+{
+	if (begin)
+		return __simple_cmd(bts, 0xA3);
+	else
+		return __simple_cmd(bts, 0xA6);
+}