diff --git a/library/GSM_RR_Types.ttcn b/library/GSM_RR_Types.ttcn
index 160ae39c3..d41e03514 100644
--- a/library/GSM_RR_Types.ttcn
+++ b/library/GSM_RR_Types.ttcn
@@ -115,6 +115,23 @@ module GSM_RR_Types {
 		INTERSYS_TO_EUTRAN_HO_CMD	('01100110'B)
 	} with { variant "FIELDLENGTH(8)" };
 
+	/* Table 10.4.2 of Section 10.4 / 3GPP TS 44.018 */
+	type enumerated RrShortDisc {
+		SYSTEM_INFORMATION_TYPE_10	('00000'B),
+		NOTIFICATION_FACCH		('00001'B),
+		UPLINK_FREE			('00010'B),
+		ENHAN_MEAS_REP_UL		('00100'B),
+		MEAS_INFO_DL			('00101'B),
+		VBS_VGCS_RECON			('00110'B),
+		VBS_VGCS_RECON2			('00111'B),
+		VGCS_ADD_INFO			('01000'B),
+		VGCS_SMS_INFO			('01001'B),
+		SYSTEM_INFORMATION_TYPE_10bis	('01010'B),
+		SYSTEM_INFORMATION_TYPE_10ter	('01011'B),
+		VGCS_NEIGH_CELL_INFO		('01100'B),
+		NOTIFY_APP_DATA			('01101'B)
+	} with { variant "FIELDLENGTH(5)" };
+
 	type enumerated RR_Cause {
 		GSM48_RR_CAUSE_NORMAL		('00'O),
 		GSM48_RR_CAUSE_ABNORMAL_UNSPEC	('01'O),