diff --git a/openbsc/src/Makefile.am b/openbsc/src/Makefile.am
index cd0a0e6..30968b0 100644
--- a/openbsc/src/Makefile.am
+++ b/openbsc/src/Makefile.am
@@ -5,16 +5,16 @@
 noinst_LIBRARIES = libbsc.a libmsc.a libvty.a
 noinst_HEADERS = vty/cardshell.h
 
-libbsc_a_SOURCES = abis_rsl.c abis_nm.c gsm_data.c \
+libbsc_a_SOURCES = abis_rsl.c abis_nm.c gsm_data.c gsm_04_08_utils.c \
 		msgb.c select.c chan_alloc.c timer.c debug.c \
-		gsm_subscriber_base.c subchan_demux.c bsc_rll.c \
+		gsm_subscriber_base.c subchan_demux.c bsc_rll.c transaction.c \
 		trau_frame.c trau_mux.c paging.c e1_config.c e1_input.c tlv_parser.c \
 		input/misdn.c input/ipaccess.c signal.c gsm_utils.c talloc.c \
 		talloc_ctx.c
 
 libmsc_a_SOURCES = gsm_subscriber.c db.c telnet_interface.c \
-		mncc.c rtp_proxy.c gsm_04_08.c gsm_04_11.c transaction.c token_auth.c \
-		rrlp.c
+		mncc.c rtp_proxy.c gsm_04_08.c gsm_04_11.c transaction.c \
+		token_auth.c rrlp.c
 
 libvty_a_SOURCES = vty/buffer.c vty/command.c vty/vector.c vty/vty.c
 
diff --git a/openbsc/src/gsm_04_08.c b/openbsc/src/gsm_04_08.c
index 46b4479..94f9ef4 100644
--- a/openbsc/src/gsm_04_08.c
+++ b/openbsc/src/gsm_04_08.c
@@ -49,18 +49,13 @@
 #include <openbsc/talloc.h>
 #include <openbsc/transaction.h>
 
-#define GSM48_ALLOC_SIZE	1024
-#define GSM48_ALLOC_HEADROOM	128
-
 #define GSM_MAX_FACILITY       128
 #define GSM_MAX_SSVERSION      128
 #define GSM_MAX_USERUSER       128
 
 void *tall_locop_ctx;
 
-/* should ip.access BTS use direct RTP streams between each other (1),
- * or should OpenBSC always act as RTP relay/proxy in between (0) ? */
-int ipacc_rtp_direct = 1;
+extern int ipacc_rtp_direct;
 
 static const struct tlv_definition rsl_att_tlvdef = {
 	.def = {
@@ -158,73 +153,6 @@
 	"illegal state 31",
 };
 
-static const char *cc_msg_names[] = {
-	"unknown 0x00",
-	"ALERTING",
-	"CALL_PROC",
-	"PROGRESS",
-	"ESTAB",
-	"SETUP",
-	"ESTAB_CONF",
-	"CONNECT",
-	"CALL_CONF",
-	"START_CC",
-	"unknown 0x0a",
-	"RECALL",
-	"unknown 0x0c",
-	"unknown 0x0d",
-	"EMERG_SETUP",
-	"CONNECT_ACK",
-	"USER_INFO",
-	"unknown 0x11",
-	"unknown 0x12",
-	"MODIFY_REJECT",
-	"unknown 0x14",
-	"unknown 0x15",
-	"unknown 0x16",
-	"MODIFY",
-	"HOLD",
-	"HOLD_ACK",
-	"HOLD_REJ",
-	"unknown 0x1b",
-	"RETR",
-	"RETR_ACK",
-	"RETR_REJ",
-	"MODIFY_COMPL",
-	"unknown 0x20",
-	"unknown 0x21",
-	"unknown 0x22",
-	"unknown 0x23",
-	"unknown 0x24",
-	"DISCONNECT",
-	"unknown 0x26",
-	"unknown 0x27",
-	"unknown 0x28",
-	"unknown 0x29",
-	"RELEASE_COMPL",
-	"unknown 0x2b",
-	"unknown 0x2c",
-	"RELEASE",
-	"unknown 0x2e",
-	"unknown 0x2f",
-	"unknown 0x30",
-	"STOP_DTMF",
-	"STOP_DTMF_ACK",
-	"unknown 0x33",
-	"STATUS_ENQ",
-	"START_DTMF",
-	"START_DTMF_ACK",
-	"START_DTMF_REJ",
-	"unknown 0x38",
-	"CONG_CTRL",
-	"FACILITY",
-	"unknown 0x3b",
-	"STATUS",
-	"unknown 0x3c",
-	"NOTIFY",
-	"unknown 0x3f",
-};
-
 static char strbuf[64];
 
 static const char *rr_cause_name(u_int8_t cause)
@@ -413,53 +341,6 @@
 	return 0;
 }
 
-static void to_bcd(u_int8_t *bcd, u_int16_t val)
-{
-	bcd[2] = val % 10;
-	val = val / 10;
-	bcd[1] = val % 10;
-	val = val / 10;
-	bcd[0] = val % 10;
-	val = val / 10;
-}
-
-void gsm0408_generate_lai(struct gsm48_loc_area_id *lai48, u_int16_t mcc, 
-			 u_int16_t mnc, u_int16_t lac)
-{
-	u_int8_t bcd[3];
-
-	to_bcd(bcd, mcc);
-	lai48->digits[0] = bcd[0] | (bcd[1] << 4);
-	lai48->digits[1] = bcd[2];
-
-	to_bcd(bcd, mnc);
-	/* FIXME: do we need three-digit MNC? See Table 10.5.3 */
-#if 0
-	lai48->digits[1] |= bcd[2] << 4;
-	lai48->digits[2] = bcd[0] | (bcd[1] << 4);
-#else
-	lai48->digits[1] |= 0xf << 4;
-	lai48->digits[2] = bcd[1] | (bcd[2] << 4);
-#endif
-	
-	lai48->lac = htons(lac);
-}
-
-#define TMSI_LEN	5
-#define MID_TMSI_LEN	(TMSI_LEN + 2)
-
-int generate_mid_from_tmsi(u_int8_t *buf, u_int32_t tmsi)
-{
-	u_int32_t *tptr = (u_int32_t *) &buf[3];
-
-	buf[0] = GSM48_IE_MOBILE_ID;
-	buf[1] = TMSI_LEN;
-	buf[2] = 0xf0 | GSM_MI_TYPE_TMSI;
-	*tptr = htonl(tmsi);
-
-	return 7;
-}
-
 static const char bcd_num_digits[] = {
 	'0', '1', '2', '3', '4', '5', '6', '7', 
 	'8', '9', '*', '#', 'a', 'b', 'c', '\0'
@@ -979,44 +860,6 @@
 	return 0;
 }
 
-struct msgb *gsm48_msgb_alloc(void)
-{
-	return msgb_alloc_headroom(GSM48_ALLOC_SIZE, GSM48_ALLOC_HEADROOM,
-				   "GSM 04.08");
-}
-
-int gsm48_sendmsg(struct msgb *msg, struct gsm_trans *trans)
-{
-	struct gsm48_hdr *gh = (struct gsm48_hdr *) msg->data;
-
-	/* if we get passed a transaction reference, do some common
-	 * work that the caller no longer has to do */
-	if (trans) {
-		gh->proto_discr = trans->protocol | (trans->transaction_id << 4);
-		msg->lchan = trans->lchan;
-	}
-
-	if (msg->lchan) {
-		msg->trx = msg->lchan->ts->trx;
-
-		if ((gh->proto_discr & GSM48_PDISC_MASK) == GSM48_PDISC_CC)
-			DEBUGP(DCC, "(bts %d trx %d ts %d ti %02x) "
-				"Sending '%s' to MS.\n", msg->trx->bts->nr,
-				msg->trx->nr, msg->lchan->ts->nr,
-				gh->proto_discr & 0xf0,
-				cc_msg_names[gh->msg_type & 0x3f]);
-		else
-			DEBUGP(DCC, "(bts %d trx %d ts %d pd %02x) "
-				"Sending 0x%02x to MS.\n", msg->trx->bts->nr,
-				msg->trx->nr, msg->lchan->ts->nr,
-				gh->proto_discr, gh->msg_type);
-	}
-
-	msg->l3h = msg->data;
-
-	return rsl_data_request(msg, 0);
-}
-
 /* Chapter 9.2.14 : Send LOCATION UPDATING REJECT */
 int gsm0408_loc_upd_rej(struct gsm_lchan *lchan, u_int8_t cause)
 {
@@ -1055,7 +898,7 @@
 	gsm0408_generate_lai(lai, bts->network->country_code,
 		     bts->network->network_code, bts->location_area_code);
 
-	mid = msgb_put(msg, MID_TMSI_LEN);
+	mid = msgb_put(msg, GSM48_MID_TMSI_LEN);
 	generate_mid_from_tmsi(mid, tmsi);
 
 	DEBUGP(DMM, "-> LOCATION UPDATE ACCEPT\n");
@@ -1091,7 +934,7 @@
 		break;
 	case GSM_MI_TYPE_TMSI:
 		/* Table 10.5.4.3, reverse generate_mid_from_tmsi */
-		if (mi_len == TMSI_LEN && mi[0] == (0xf0 | GSM_MI_TYPE_TMSI)) {
+		if (mi_len == GSM48_TMSI_LEN && mi[0] == (0xf0 | GSM_MI_TYPE_TMSI)) {
 			memcpy(&tmsi, &mi[1], 4);
 			tmsi = ntohl(tmsi);
 			return snprintf(string, str_len, "%u", tmsi);
@@ -1891,30 +1734,6 @@
 	return rc;
 }
 
-/* 7.1.7 and 9.1.7: RR CHANnel RELease */
-int gsm48_send_rr_release(struct gsm_lchan *lchan)
-{
-	struct msgb *msg = gsm48_msgb_alloc();
-	struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
-	u_int8_t *cause;
-
-	msg->lchan = lchan;
-	gh->proto_discr = GSM48_PDISC_RR;
-	gh->msg_type = GSM48_MT_RR_CHAN_REL;
-
-	cause = msgb_put(msg, 1);
-	cause[0] = GSM48_RR_CAUSE_NORMAL;
-
-	DEBUGP(DRR, "Sending Channel Release: Chan: Number: %d Type: %d\n",
-		lchan->nr, lchan->type);
-
-	/* Send actual release request to MS */
-	gsm48_sendmsg(msg, NULL);
-	/* FIXME: Start Timer T3109 */
-
-	/* Deactivate the SACCH on the BTS side */
-	return rsl_deact_sacch(lchan);
-}
 
 int gsm48_send_rr_app_info(struct gsm_lchan *lchan, u_int8_t apdu_id,
 			   u_int8_t apdu_len, u_int8_t *apdu)
@@ -3756,7 +3575,7 @@
 		"Received '%s' from MS in state %d (%s)\n",
 		lchan->ts->trx->bts->nr, lchan->ts->trx->nr, lchan->ts->nr,
 		transaction_id, (lchan->subscr)?(lchan->subscr->extension):"-",
-		cc_msg_names[msg_type], trans?(trans->cc.state):0,
+		gsm0408_cc_msg_names[msg_type], trans?(trans->cc.state):0,
 		cc_state_names[trans?(trans->cc.state):0]);
 
 	/* Create transaction */
@@ -3827,99 +3646,6 @@
 	return rc;
 }
 
-/* Section 9.1.8 / Table 9.9 */
-struct chreq {
-	u_int8_t val;
-	u_int8_t mask;
-	enum chreq_type type;
-};
-
-/* If SYSTEM INFORMATION TYPE 4 NECI bit == 1 */
-static const struct chreq chreq_type_neci1[] = {
-	{ 0xa0, 0xe0, CHREQ_T_EMERG_CALL },
-	{ 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_F },
-	{ 0x68, 0xfc, CHREQ_T_CALL_REEST_TCH_H },
-	{ 0x6c, 0xfc, CHREQ_T_CALL_REEST_TCH_H_DBL },
-	{ 0xe0, 0xe0, CHREQ_T_SDCCH },
-	{ 0x40, 0xf0, CHREQ_T_VOICE_CALL_TCH_H },
-	{ 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H },
-	{ 0x00, 0xf0, CHREQ_T_LOCATION_UPD },
-	{ 0x10, 0xf0, CHREQ_T_SDCCH },
-	{ 0x80, 0xe0, CHREQ_T_PAG_R_ANY },
-	{ 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F },
-	{ 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH },
-};
-
-/* If SYSTEM INFORMATION TYPE 4 NECI bit == 0 */
-static const struct chreq chreq_type_neci0[] = {
-	{ 0xa0, 0xe0, CHREQ_T_EMERG_CALL },
-	{ 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_H },
-	{ 0xe0, 0xe0, CHREQ_T_TCH_F },
-	{ 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H },
-	{ 0x00, 0xe0, CHREQ_T_LOCATION_UPD },
-	{ 0x80, 0xe0, CHREQ_T_PAG_R_ANY },
-	{ 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F },
-	{ 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH },
-};
-
-static const enum gsm_chan_t ctype_by_chreq[] = {
-	[CHREQ_T_EMERG_CALL]		= GSM_LCHAN_TCH_F,
-	[CHREQ_T_CALL_REEST_TCH_F]	= GSM_LCHAN_TCH_F,
-	[CHREQ_T_CALL_REEST_TCH_H]	= GSM_LCHAN_TCH_H,
-	[CHREQ_T_CALL_REEST_TCH_H_DBL]	= GSM_LCHAN_TCH_H,
-	[CHREQ_T_SDCCH]			= GSM_LCHAN_SDCCH,
-	[CHREQ_T_TCH_F]			= GSM_LCHAN_TCH_F,
-	[CHREQ_T_VOICE_CALL_TCH_H]	= GSM_LCHAN_TCH_H,
-	[CHREQ_T_DATA_CALL_TCH_H]	= GSM_LCHAN_TCH_H,
-	[CHREQ_T_LOCATION_UPD]		= GSM_LCHAN_SDCCH,
-	[CHREQ_T_PAG_R_ANY]		= GSM_LCHAN_SDCCH,
-	[CHREQ_T_PAG_R_TCH_F]		= GSM_LCHAN_TCH_F,
-	[CHREQ_T_PAG_R_TCH_FH]		= GSM_LCHAN_TCH_F,
-};
-
-static const enum gsm_chreq_reason_t reason_by_chreq[] = {
-	[CHREQ_T_EMERG_CALL]		= GSM_CHREQ_REASON_EMERG,
-	[CHREQ_T_CALL_REEST_TCH_F]	= GSM_CHREQ_REASON_CALL,
-	[CHREQ_T_CALL_REEST_TCH_H]	= GSM_CHREQ_REASON_CALL,
-	[CHREQ_T_CALL_REEST_TCH_H_DBL]	= GSM_CHREQ_REASON_CALL,
-	[CHREQ_T_SDCCH]			= GSM_CHREQ_REASON_OTHER,
-	[CHREQ_T_TCH_F]			= GSM_CHREQ_REASON_OTHER,
-	[CHREQ_T_VOICE_CALL_TCH_H]	= GSM_CHREQ_REASON_OTHER,
-	[CHREQ_T_DATA_CALL_TCH_H]	= GSM_CHREQ_REASON_OTHER,
-	[CHREQ_T_LOCATION_UPD]		= GSM_CHREQ_REASON_LOCATION_UPD,
-	[CHREQ_T_PAG_R_ANY]		= GSM_CHREQ_REASON_PAG,
-	[CHREQ_T_PAG_R_TCH_F]		= GSM_CHREQ_REASON_PAG,
-	[CHREQ_T_PAG_R_TCH_FH]		= GSM_CHREQ_REASON_PAG,
-};
-
-enum gsm_chan_t get_ctype_by_chreq(struct gsm_bts *bts, u_int8_t ra)
-{
-	int i;
-	/* FIXME: determine if we set NECI = 0 in the BTS SI4 */
-
-	for (i = 0; i < ARRAY_SIZE(chreq_type_neci0); i++) {
-		const struct chreq *chr = &chreq_type_neci0[i];
-		if ((ra & chr->mask) == chr->val)
-			return ctype_by_chreq[chr->type];
-	}
-	fprintf(stderr, "Unknown CHANNEL REQUEST RQD 0x%02x\n", ra);
-	return GSM_LCHAN_SDCCH;
-}
-
-enum gsm_chreq_reason_t get_reason_by_chreq(struct gsm_bts *bts, u_int8_t ra)
-{
-	int i;
-	/* FIXME: determine if we set NECI = 0 in the BTS SI4 */
-
-	for (i = 0; i < ARRAY_SIZE(chreq_type_neci0); i++) {
-		const struct chreq *chr = &chreq_type_neci0[i];
-		if ((ra & chr->mask) == chr->val)
-			return reason_by_chreq[chr->type];
-	}
-	fprintf(stderr, "Unknown CHANNEL REQUEST REASON 0x%02x\n", ra);
-	return GSM_CHREQ_REASON_OTHER;
-}
-
 /* dequeue messages to layer 4 */
 int bsc_upqueue(struct gsm_network *net)
 {
diff --git a/openbsc/src/gsm_04_08_utils.c b/openbsc/src/gsm_04_08_utils.c
new file mode 100644
index 0000000..50deb2b
--- /dev/null
+++ b/openbsc/src/gsm_04_08_utils.c
@@ -0,0 +1,310 @@
+/* GSM Mobile Radio Interface Layer 3 messages on the A-bis interface
+ * 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0
+ * utility functions
+ */
+
+/* (C) 2008-2009 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2008, 2009 by Holger Hans Peter Freyther <zecke@selfish.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 <stdio.h>
+#include <stdlib.h>
+#include <netinet/in.h>
+
+#include <openbsc/msgb.h>
+#include <openbsc/debug.h>
+#include <openbsc/gsm_04_08.h>
+#include <openbsc/transaction.h>
+
+#define GSM48_ALLOC_SIZE	1024
+#define GSM48_ALLOC_HEADROOM	128
+
+/* should ip.access BTS use direct RTP streams between each other (1),
+ * or should OpenBSC always act as RTP relay/proxy in between (0) ? */
+int ipacc_rtp_direct = 1;
+
+
+const char *gsm0408_cc_msg_names[] = {
+	"unknown 0x00",
+	"ALERTING",
+	"CALL_PROC",
+	"PROGRESS",
+	"ESTAB",
+	"SETUP",
+	"ESTAB_CONF",
+	"CONNECT",
+	"CALL_CONF",
+	"START_CC",
+	"unknown 0x0a",
+	"RECALL",
+	"unknown 0x0c",
+	"unknown 0x0d",
+	"EMERG_SETUP",
+	"CONNECT_ACK",
+	"USER_INFO",
+	"unknown 0x11",
+	"unknown 0x12",
+	"MODIFY_REJECT",
+	"unknown 0x14",
+	"unknown 0x15",
+	"unknown 0x16",
+	"MODIFY",
+	"HOLD",
+	"HOLD_ACK",
+	"HOLD_REJ",
+	"unknown 0x1b",
+	"RETR",
+	"RETR_ACK",
+	"RETR_REJ",
+	"MODIFY_COMPL",
+	"unknown 0x20",
+	"unknown 0x21",
+	"unknown 0x22",
+	"unknown 0x23",
+	"unknown 0x24",
+	"DISCONNECT",
+	"unknown 0x26",
+	"unknown 0x27",
+	"unknown 0x28",
+	"unknown 0x29",
+	"RELEASE_COMPL",
+	"unknown 0x2b",
+	"unknown 0x2c",
+	"RELEASE",
+	"unknown 0x2e",
+	"unknown 0x2f",
+	"unknown 0x30",
+	"STOP_DTMF",
+	"STOP_DTMF_ACK",
+	"unknown 0x33",
+	"STATUS_ENQ",
+	"START_DTMF",
+	"START_DTMF_ACK",
+	"START_DTMF_REJ",
+	"unknown 0x38",
+	"CONG_CTRL",
+	"FACILITY",
+	"unknown 0x3b",
+	"STATUS",
+	"unknown 0x3c",
+	"NOTIFY",
+	"unknown 0x3f",
+};
+
+
+struct msgb *gsm48_msgb_alloc(void)
+{
+	return msgb_alloc_headroom(GSM48_ALLOC_SIZE, GSM48_ALLOC_HEADROOM,
+				   "GSM 04.08");
+}
+
+int gsm48_sendmsg(struct msgb *msg, struct gsm_trans *trans)
+{
+	struct gsm48_hdr *gh = (struct gsm48_hdr *) msg->data;
+
+	/* if we get passed a transaction reference, do some common
+	 * work that the caller no longer has to do */
+	if (trans) {
+		gh->proto_discr = trans->protocol | (trans->transaction_id << 4);
+		msg->lchan = trans->lchan;
+	}
+
+	if (msg->lchan) {
+		msg->trx = msg->lchan->ts->trx;
+
+		if ((gh->proto_discr & GSM48_PDISC_MASK) == GSM48_PDISC_CC)
+			DEBUGP(DCC, "(bts %d trx %d ts %d ti %02x) "
+				"Sending '%s' to MS.\n", msg->trx->bts->nr,
+				msg->trx->nr, msg->lchan->ts->nr,
+				gh->proto_discr & 0xf0,
+				gsm0408_cc_msg_names[gh->msg_type & 0x3f]);
+		else
+			DEBUGP(DCC, "(bts %d trx %d ts %d pd %02x) "
+				"Sending 0x%02x to MS.\n", msg->trx->bts->nr,
+				msg->trx->nr, msg->lchan->ts->nr,
+				gh->proto_discr, gh->msg_type);
+	}
+
+	msg->l3h = msg->data;
+
+	return rsl_data_request(msg, 0);
+}
+
+static void to_bcd(u_int8_t *bcd, u_int16_t val)
+{
+	bcd[2] = val % 10;
+	val = val / 10;
+	bcd[1] = val % 10;
+	val = val / 10;
+	bcd[0] = val % 10;
+	val = val / 10;
+}
+
+void gsm0408_generate_lai(struct gsm48_loc_area_id *lai48, u_int16_t mcc,
+			 u_int16_t mnc, u_int16_t lac)
+{
+	u_int8_t bcd[3];
+
+	to_bcd(bcd, mcc);
+	lai48->digits[0] = bcd[0] | (bcd[1] << 4);
+	lai48->digits[1] = bcd[2];
+
+	to_bcd(bcd, mnc);
+	/* FIXME: do we need three-digit MNC? See Table 10.5.3 */
+#if 0
+	lai48->digits[1] |= bcd[2] << 4;
+	lai48->digits[2] = bcd[0] | (bcd[1] << 4);
+#else
+	lai48->digits[1] |= 0xf << 4;
+	lai48->digits[2] = bcd[1] | (bcd[2] << 4);
+#endif
+
+	lai48->lac = htons(lac);
+}
+
+int generate_mid_from_tmsi(u_int8_t *buf, u_int32_t tmsi)
+{
+	u_int32_t *tptr = (u_int32_t *) &buf[3];
+
+	buf[0] = GSM48_IE_MOBILE_ID;
+	buf[1] = GSM48_TMSI_LEN;
+	buf[2] = 0xf0 | GSM_MI_TYPE_TMSI;
+	*tptr = htonl(tmsi);
+
+	return 7;
+}
+
+/* Section 9.1.8 / Table 9.9 */
+struct chreq {
+	u_int8_t val;
+	u_int8_t mask;
+	enum chreq_type type;
+};
+
+/* If SYSTEM INFORMATION TYPE 4 NECI bit == 1 */
+static const struct chreq chreq_type_neci1[] = {
+	{ 0xa0, 0xe0, CHREQ_T_EMERG_CALL },
+	{ 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_F },
+	{ 0x68, 0xfc, CHREQ_T_CALL_REEST_TCH_H },
+	{ 0x6c, 0xfc, CHREQ_T_CALL_REEST_TCH_H_DBL },
+	{ 0xe0, 0xe0, CHREQ_T_SDCCH },
+	{ 0x40, 0xf0, CHREQ_T_VOICE_CALL_TCH_H },
+	{ 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H },
+	{ 0x00, 0xf0, CHREQ_T_LOCATION_UPD },
+	{ 0x10, 0xf0, CHREQ_T_SDCCH },
+	{ 0x80, 0xe0, CHREQ_T_PAG_R_ANY },
+	{ 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F },
+	{ 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH },
+};
+
+/* If SYSTEM INFORMATION TYPE 4 NECI bit == 0 */
+static const struct chreq chreq_type_neci0[] = {
+	{ 0xa0, 0xe0, CHREQ_T_EMERG_CALL },
+	{ 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_H },
+	{ 0xe0, 0xe0, CHREQ_T_TCH_F },
+	{ 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H },
+	{ 0x00, 0xe0, CHREQ_T_LOCATION_UPD },
+	{ 0x80, 0xe0, CHREQ_T_PAG_R_ANY },
+	{ 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F },
+	{ 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH },
+};
+
+static const enum gsm_chan_t ctype_by_chreq[] = {
+	[CHREQ_T_EMERG_CALL]		= GSM_LCHAN_TCH_F,
+	[CHREQ_T_CALL_REEST_TCH_F]	= GSM_LCHAN_TCH_F,
+	[CHREQ_T_CALL_REEST_TCH_H]	= GSM_LCHAN_TCH_H,
+	[CHREQ_T_CALL_REEST_TCH_H_DBL]	= GSM_LCHAN_TCH_H,
+	[CHREQ_T_SDCCH]			= GSM_LCHAN_SDCCH,
+	[CHREQ_T_TCH_F]			= GSM_LCHAN_TCH_F,
+	[CHREQ_T_VOICE_CALL_TCH_H]	= GSM_LCHAN_TCH_H,
+	[CHREQ_T_DATA_CALL_TCH_H]	= GSM_LCHAN_TCH_H,
+	[CHREQ_T_LOCATION_UPD]		= GSM_LCHAN_SDCCH,
+	[CHREQ_T_PAG_R_ANY]		= GSM_LCHAN_SDCCH,
+	[CHREQ_T_PAG_R_TCH_F]		= GSM_LCHAN_TCH_F,
+	[CHREQ_T_PAG_R_TCH_FH]		= GSM_LCHAN_TCH_F,
+};
+
+static const enum gsm_chreq_reason_t reason_by_chreq[] = {
+	[CHREQ_T_EMERG_CALL]		= GSM_CHREQ_REASON_EMERG,
+	[CHREQ_T_CALL_REEST_TCH_F]	= GSM_CHREQ_REASON_CALL,
+	[CHREQ_T_CALL_REEST_TCH_H]	= GSM_CHREQ_REASON_CALL,
+	[CHREQ_T_CALL_REEST_TCH_H_DBL]	= GSM_CHREQ_REASON_CALL,
+	[CHREQ_T_SDCCH]			= GSM_CHREQ_REASON_OTHER,
+	[CHREQ_T_TCH_F]			= GSM_CHREQ_REASON_OTHER,
+	[CHREQ_T_VOICE_CALL_TCH_H]	= GSM_CHREQ_REASON_OTHER,
+	[CHREQ_T_DATA_CALL_TCH_H]	= GSM_CHREQ_REASON_OTHER,
+	[CHREQ_T_LOCATION_UPD]		= GSM_CHREQ_REASON_LOCATION_UPD,
+	[CHREQ_T_PAG_R_ANY]		= GSM_CHREQ_REASON_PAG,
+	[CHREQ_T_PAG_R_TCH_F]		= GSM_CHREQ_REASON_PAG,
+	[CHREQ_T_PAG_R_TCH_FH]		= GSM_CHREQ_REASON_PAG,
+};
+
+enum gsm_chan_t get_ctype_by_chreq(struct gsm_bts *bts, u_int8_t ra)
+{
+	int i;
+	/* FIXME: determine if we set NECI = 0 in the BTS SI4 */
+
+	for (i = 0; i < ARRAY_SIZE(chreq_type_neci0); i++) {
+		const struct chreq *chr = &chreq_type_neci0[i];
+		if ((ra & chr->mask) == chr->val)
+			return ctype_by_chreq[chr->type];
+	}
+	fprintf(stderr, "Unknown CHANNEL REQUEST RQD 0x%02x\n", ra);
+	return GSM_LCHAN_SDCCH;
+}
+
+enum gsm_chreq_reason_t get_reason_by_chreq(struct gsm_bts *bts, u_int8_t ra)
+{
+	int i;
+	/* FIXME: determine if we set NECI = 0 in the BTS SI4 */
+
+	for (i = 0; i < ARRAY_SIZE(chreq_type_neci0); i++) {
+		const struct chreq *chr = &chreq_type_neci0[i];
+		if ((ra & chr->mask) == chr->val)
+			return reason_by_chreq[chr->type];
+	}
+	fprintf(stderr, "Unknown CHANNEL REQUEST REASON 0x%02x\n", ra);
+	return GSM_CHREQ_REASON_OTHER;
+}
+
+/* 7.1.7 and 9.1.7: RR CHANnel RELease */
+int gsm48_send_rr_release(struct gsm_lchan *lchan)
+{
+	struct msgb *msg = gsm48_msgb_alloc();
+	struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
+	u_int8_t *cause;
+
+	msg->lchan = lchan;
+	gh->proto_discr = GSM48_PDISC_RR;
+	gh->msg_type = GSM48_MT_RR_CHAN_REL;
+
+	cause = msgb_put(msg, 1);
+	cause[0] = GSM48_RR_CAUSE_NORMAL;
+
+	DEBUGP(DRR, "Sending Channel Release: Chan: Number: %d Type: %d\n",
+		lchan->nr, lchan->type);
+
+	/* Send actual release request to MS */
+	gsm48_sendmsg(msg, NULL);
+	/* FIXME: Start Timer T3109 */
+
+	/* Deactivate the SACCH on the BTS side */
+	return rsl_deact_sacch(lchan);
+}
+