diff --git a/include/osmocom/gsm/protocol/gsm_12_21.h b/include/osmocom/gsm/protocol/gsm_12_21.h
index 86d12ea..06755c9 100644
--- a/include/osmocom/gsm/protocol/gsm_12_21.h
+++ b/include/osmocom/gsm/protocol/gsm_12_21.h
@@ -511,6 +511,7 @@
 
 	/* osmocom (osmo-bts) specific attributes, used in combination
 	 * with the "org.osmocom" manufacturer identification */
+	NM_ATT_OSMO_NS_LINK_CFG         = 0xfd, /* osmocom version supports IPv4 & IPv6 in difference to IPACC */
 	NM_ATT_OSMO_REDUCEPOWER		= 0xfe,	/* TLV_TYPE_TV */
 };
 #define NM_ATT_BS11_FILE_DATA	NM_ATT_EVENT_TYPE
diff --git a/src/gsm/abis_nm.c b/src/gsm/abis_nm.c
index 3fb8f0f..13837d2 100644
--- a/src/gsm/abis_nm.c
+++ b/src/gsm/abis_nm.c
@@ -589,6 +589,7 @@
 /*! org.osmocom GSM A-bis OML TLV parser definition */
 const struct tlv_definition abis_nm_osmo_att_tlvdef = {
 	.def = {
+		[NM_ATT_OSMO_NS_LINK_CFG] =	{ TLV_TYPE_TL16V },
 		[NM_ATT_OSMO_REDUCEPOWER] =	{ TLV_TYPE_TV },
 	},
 };