add SGs / CSFB related dot + msc files
Those graphs + message sequence charts are not yet used by any
of our manuals, but they should become used by the OsmoMSC user
manual once SGs interface support is added.
Related: OS#2583
Change-Id: Idfd3a66c18131b5458d183b8e66f62eaaab65991
diff --git a/doc/manuals/images/sgs-mt_sms_idle.msc b/doc/manuals/images/sgs-mt_sms_idle.msc
new file mode 100644
index 0000000..7b453e0
--- /dev/null
+++ b/doc/manuals/images/sgs-mt_sms_idle.msc
@@ -0,0 +1,22 @@
+msc {
+ hscale=2;
+ UE, MME, VLR [label="MSC/VLR"], HSS [label="HSS/HLR"], SMSC;
+
+ UE box HSS [label="EPS/IMSI attach procedure"];
+ ...;
+
+ VLR <= SMSC [label="MAP/GSUP ForwardSM"];
+ MME <= VLR [label="SGsAP PAGING"];
+ UE <= MME [label="Paging"];
+ UE box MME [label="Service Request"];
+ MME => VLR [label="SGsAP SERVICE REQ"];
+ MME <= VLR [label="SGsAP DL UNITDATA\n(CP-DATA/RP-DATA/TPDU)"];
+ UE <= MME [label="DL NAS Transport"];
+ UE => MME [label="UL NAS Transport"];
+ MME => VLR [label="SGsAP UL UNITDATA"];
+ ...;
+ UE => MME [label="UL NAS Transport"];
+ MME => VLR [label="SGsAP UL UNITDATA"];
+ VLR => SMSC [label="Delivery report"];
+ MME <= VLR [label="SGsAP RELEASE REQ"];
+}