From 0c076bc75a64c0d6db22171ae42673b1e3cbd346 Mon Sep 17 00:00:00 2001
From: Neels Hofmeyr <neels@hofmeyr.de>
Date: Tue, 27 Jul 2021 23:30:48 +0200
Subject: [PATCH] add sequence_charts/call_reestablishment.msc

Change-Id: I6ebc3a0555ef82e1c027ca75b45f8147a3e07ee6
---
 doc/sequence_charts/Makefile.am              |  2 ++
 doc/sequence_charts/call_reestablishment.msc | 33 ++++++++++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 doc/sequence_charts/call_reestablishment.msc

diff --git a/doc/sequence_charts/Makefile.am b/doc/sequence_charts/Makefile.am
index 6782f44e7..5efe8558b 100644
--- a/doc/sequence_charts/Makefile.am
+++ b/doc/sequence_charts/Makefile.am
@@ -7,6 +7,7 @@ EXTRA_DIST = \
 	inter_bsc_ho.msc \
 	inter_msc_ho.msc \
 	mncc_call_fsm.msc \
+	call_reestablishment.msc \
 	$(NULL)
 
 CLEANFILES = \
@@ -21,6 +22,7 @@ msc: \
 	$(builddir)/inter_bsc_ho.png \
 	$(builddir)/inter_msc_ho.png \
 	$(builddir)/voice_call_full.png \
+	$(builddir)/call_reestablishment.png \
 	$(NULL)
 
 dot: \
diff --git a/doc/sequence_charts/call_reestablishment.msc b/doc/sequence_charts/call_reestablishment.msc
new file mode 100644
index 000000000..b4d081ca2
--- /dev/null
+++ b/doc/sequence_charts/call_reestablishment.msc
@@ -0,0 +1,33 @@
+msc {
+  hscale="2";
+  ms[label="MS"],cell1[label="Cell 1 (BTS+BSC)"],cell0[label="Cell 0 (BTS+BSC)"],__msc[label="MSC"];
+
+  ms rbox __msc [label="Call Re-Establishment"];
+  ms note __msc [label="Ongoing voice call: MM is established"];
+
+  ...;
+
+  ms -x cell0 [label="radio link fails"];
+  ms x- cell0;
+
+  __msc abox __msc [label="Keep MM until timeout"];
+
+  ms => cell1 [label="Channel Required"];
+  ms <= cell1 [label="Immediate Assignment"];
+  ms => cell1 [label="Complete Layer3"];
+  cell1 => __msc [label="Complete Layer3:\nCM Re-Establishment Request"];
+
+  cell0 <= __msc [label="Clear Command"];
+  cell0 => __msc [label="Clear Complete"];
+
+  cell1 <= __msc [label="Authentication Request"];
+  cell1 => __msc [label="Authentication Response"];
+
+  cell1 <= __msc [label="Cipher Mode Commad"];
+  cell1 => __msc [label="Cipher Mode Complete"];
+
+  cell1 <= __msc [label="Assignment Request\nthis Assignment ACKs the CM Re-Establishment"];
+  ms <= cell1 [label="RR Assignment Command"];
+  ms => cell1 [label="RR Assignment Complete"];
+  cell1 => __msc [label="Assignment Complete"];
+}