import message sequence charts (ladder diagrams) for RUA/RANAP/NAS
diff --git a/doc/hnb_cs_mo_call.msc b/doc/hnb_cs_mo_call.msc
new file mode 100644
index 0000000..a9253c0
--- /dev/null
+++ b/doc/hnb_cs_mo_call.msc
@@ -0,0 +1,75 @@
+msc {
+ hscale = "3";
+ ue,hnb,hnbgw,cn;
+
+ ue box hnb [ label = "Radio Channel Establishment" ];
+ ue => hnb [ label = "RRC (CM SERV REQ)" ] ;
+ hnb => hnbgw [ label = "RUA CONNECT (RANAP Initial UE Msg (CM SERV REQ))" ];
+ hnbgw => cn [ label = "SCCP CR (RANAP Initial UE Msg (CM SERV REQ))" ];
+ cn >> hnbgw [ label = "SCCP CC" ];
+
+ --- [ label = "Optional retrieval of IMSI (if not given in CM or retrived from VLR by TMSI)" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP DirectTransfer (MM IDENTITY REQ))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP DirectTransfer (MM IDENTITY REQ))" ];
+ hnb => ue [ label = "RRC (MM IDENTITY REQ)" ];
+ ue >> hnb [ label = "RRC (MM IDENTITY RESP)" ];
+ hnb >> hnbgw [ label = "RUA DT (RANAP DirectTransfer (MM IDENTITY RESP))" ];
+ hnbgw >> cn [ label = "SCCP DT1 (RANAP DirectTransfer (MM IDENTITY RESP))" ];
+
+ --- [ label = "Mandatory activation of Integrity Protection" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP SecurityModeCommand (IK))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP SecurityModeCommand (IK))" ];
+ hnb >> hnbgw [ label = "RUA DT (RANAP SecurityModeResponse (IK))" ];
+ hnbgw >> cn [ label = "SCCP DT1 (RANAP SecurityModeResponse (IK))" ];
+
+ cn => hnbgw [ label = "SCCP DT1 (RANAP CommonID)" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP CommonID)" ];
+
+ --- [ label = "Optional Authentication" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP DirectTransfer (MM AUTH REQ))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP DirectTransfer (MM AUTH REQ))" ];
+ hnb => ue [ label = "RRC (MM AUTH REQ)" ];
+ ue >> hnb [ label = "RRC (MM AUTH RESP)" ];
+ hnb >> hnbgw [ label = "RUA DT (RANAP DirectTransfer (MM AUTH RESP))" ];
+ hnbgw >> cn [ label = "SCCP DT1 (RANAP DirectTransfer (MM AUTH RESP))" ];
+
+ --- [ label = "Optional activation of Encryption" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP SecurityModeCommand (IK+CK))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP SecurityModeCommand (IK+CK))" ];
+ hnb >> hnbgw [ label = "RUA DT (RANAP SecurityModeResponse (IK+CK))" ];
+ hnbgw >> cn [ label = "SCCP DT1 (RANAP SecurityModeResponse (IK+CK))" ];
+
+ cn >> hnbgw [ label = "SCCP DT1 (RANAP DirectTransfer (CM SERV ACC))" ];
+ hnbgw >> hnb [ label = "RUA DT (RANAP DirectTransfer (CM SERV ACC))" ];
+ hnb >> ue [ label = "RRC (CM SERV ACC)" ];
+
+ ue box ue [ label = "subscriber A dials a call" ];
+ ue => hnb [ label = "RRC (CC SETUP)" ];
+ hnb => hnbgw [ label = "RUA DT (RANAP DirectTransfer (CC SETUP))" ];
+ hnbgw => cn [ label = "SCCP DT1 (RANAP DirectTransfer (CC SETUP))" ];
+
+ cn box cn [ label = "Signalling towards B subscriber via ISUP, SIP, ..." ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP DirectTransfer (CC ALERTING))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP DirectTransfer (CC ALERTING))" ];
+ hnb => ue [ label = "RC (CC ALERTING)" ];
+
+ --- [ label = "Assignment of Voice Channel" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP RAB Assign Cmd)" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP RAB Assign Cmd)" ];
+ hnb >> hnbgw [ label = "RUA DT (RANAP RAB Assign Rsp)" ];
+ hnbgw >> cn [ label = "SCCP DT1 (RANAP RAB Assign Rsp)" ];
+
+ cn box cn [ label = "subscriber B picks up the ringing call" ];
+ cn => hnbgw [ label = "SCCP DT1 (RANAP DirectTransfer (CC CALL CONF))" ];
+ hnbgw => hnb [ label = "RUA DT (RANAP DirectTransfer (CC CALL CONF))" ];
+ hnb => ue [ label = "RRC (CC CALL CONF)" ];
+
+ cn box ue [ label = "Voice channel open" ];
+
+ ue box ue [ label = "subscriber A hangs up" ];
+ ue => hnb [ label = "RRC (CC DISCONNECT)" ];
+ hnb => hnbgw [ label = "RUA DT (RANAP DirectTranfer (CC DISCONNECT))" ];
+ hnbgw => cn [ label = "SCCP DT1 (RANAP DirectTranfer (CC DISCONNECT))" ];
+
+ cn box hnb [ label = "RAB Release or Iu Release" ];
+}