[handover] Implement 04.08 HANDOVER COMMAND
This is needed by a yet-to-be-implemented handover algorithm, after
it has allocated a new lchan for the MS. Also missing: handling
the actual HANDOVER COMPLETE / FAIL messages in response.
diff --git a/openbsc/doc/handover.txt b/openbsc/doc/handover.txt
index 524d386..ac19e87 100644
--- a/openbsc/doc/handover.txt
+++ b/openbsc/doc/handover.txt
@@ -75,3 +75,15 @@
* RXQUAL >= 6: 1 dB
+
+== Actual Handover on a protocol level ==
+
+After the BSC has decided a handover shall be done, it has to
+
+# allocate a channel at the new BTS
+# allocate a handover reference
+# activate the channel on the BTS side using RSL CHANNEL ACTIVATION,
+ indicating the HO reference
+# BTS responds with CHAN ACT ACK, including GSM frame number
+# BSC sends 04.08 HO CMD to MS using old BTS
+