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add message sequence chart MS/BTS/BSC/MSC for 3GPP aoIP MO call 

Change-Id: I7e41234cfe1483bb73589dc959851a54f9aafa36
This commit is contained in:
Harald Welte 2017-12-21 20:57:27 +01:00 committed by Neels Hofmeyr
parent d22e31fc9b
commit 3a6ad2a2a2
1 changed files with 146 additions and 0 deletions
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146
doc/manuals/message-sequences/mo_call-abis_a.msc Normal file
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msc {
hscale=2;
ms [label="MS"],
bts [label="BTS"],
bsc_l [label="BSC(lchan SDCCH)"],
bsc_l2 [label="BSC(lchan TCH)"],
bsc [label="BSC"],
mgw [label="MGW@BSC"],
m_sc [label="MSC"];
...;
--- [label="MS Requests dedicated channel"];
ms -> bts [label="RACH: REQ"];
bts -> bsc [label="RSL Cchan CHAN RQD"];
bsc_l <= bsc [label="allocate lchan (RR IMM ASS)", textcolor="red", linecolor="red"];
bts <- bsc_l [label="RSL Dchan (SDCCH) CHAN ACT"];
bts -> bsc_l [label="RSL Dchan (SDCCH) CHAN ACT ACK"];
bts <- bsc_l [label="RSL Cchan IMM ASS (RR IMM ASS)"];
bsc_l box bsc_l [label="Start T3101"];
ms <- bts [label="AGCH: RR IMM ASS"];
--- [label="MS Establishes SDCCH"];
ms -> bts [label="SDCCH: SABM (CM SERV REQ)"];
ms <- bts [label="SDCCH: UA (CM SERV REQ)"];
bts -> bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) EST IND", textcolor="green", linecolor="green"];
bsc_l box bsc_l [label="Stop T3101"];
bsc_l => bsc [label="GSCON_EV_A_CONN_REQ", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP CR (BSSMAP COMPL L3 (CM SERV REQ))"];
bsc <- m_sc [label="SCCP CC"];
bsc -> bsc [label="GSCON_EV_A_CONN_CFM", textcolor="red", linecolor="red"];
ms box m_sc [label="Authentication, MM info, ..."];
bsc <- m_sc [label="SCCP DT1 (DTAP (CM SERV ACK)"];
bsc -> bsc [label="GSCON_EV_MT_DTAP", textcolor="red", linecolor="red"];
bsc_l <= bsc [label="lchan_submit_dtap(CM SERV ACK)", textcolor="red", linecolor="red"];
bts <- bsc_l [label="RSL RLL (SDCCH) DATA REQ (CM SERV ACK)", textcolor="green", linecolor="green"];
ms <- bts [label="SDCCH: I (CM SERV ACK)"];
ms -> bts [label="SDCCH: I (CC SETUP)"];
bts -> bsc_l [label="RSL RLL (SDCCH) DATA IND (CC SETUP)", textcolor="green", linecolor="green"];
bsc_l -> bsc [label="GSCON_EV_MO_DTAP", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP DT1 (DTAP (CC SETUP))"];
...;
--- [label="MSC assigns Voice Channel (TCH)"];
bsc <- m_sc [label="SCCP DT1 (BSSMAP ASSIGNMENT CMD)"];
bsc -> bsc [label="GSCON_EV_A_ASSIGNMENT_CMD", textcolor="red", linecolor="red"];
bsc_l2 <= bsc [label="allocate lchan", textcolor="red", linecolor="red"];
bts <- bsc_l2 [label="RSL Dchan (TCH) CHAN ACT"];
bts -> bsc_l2 [label="RSL Dchan (TCH) CHAN ACT ACK"];
bts <- bsc_l [label="RSL RLL (SDDCH) DATA REQ (RR ASSIGNMENT CMD)", textcolor="green",
linecolor="green"];
bsc_l2 box bsc_l2 [label="Start T3107"];
ms <- bts [label="SDCCH: I (RR ASSIGNMENT CMD)"];
ms box ms [label="local-end RLL release", textcolor="green", linecolor="green"];
bts -> bsc_l [label="RSL RLL (SDCCH) REL IND", textcolor="gray", linecolor="green"];
bsc_l => bsc [label="GSCON_EV_RLL_REL_IND", textcolor="gray", linecolor="red"];
bts -> bsc_l [label="RSL Dchan (SDCCH) CONN FAIL IND", textcolor="gray", linecolor="green"];
bsc_l => bsc [label="GSCON_EV_CONN_FAIL", textcolor="gray", linecolor="red"];
bsc_l box bsc_l [label="BSC must ignore failures on old channel"];
ms -> bts [label="TCH: SABM (RR ASSIGNMENT CMPL)"];
ms <- bts [label="TCH: UA (RR ASSIGNMENT CMPL)"];
bts -> bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) EST IND", textcolor="green", linecolor="green"];
bsc_l2 box bsc_l2 [label="Stop T3107"];
bsc_l2 => bsc [label="GSCON_EV_RR_ASS_COMPL", textcolor="red", linecolor="red"];
bsc_l <= bsc [label="release_lchan(SDCCH)", textcolor="red", linecolor="red"];
bts box bsc_l [label="local-end RLL release", textcolor="green", linecolor="green"];
bts <- bsc_l [label="RSL Dchan (SDCCH) RF CHAN REL"];
bts <- bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) REL REQ", textcolor="gray", linecolor="green"];
bts <- bsc_l [label="RSL DChan (SDCCH) DEACTIVATE SACCH", textcolor="gray", linecolor="black"];
bts -> bsc_l [label="RSL RLL (SDCCH, SAPI0, DCCH) RF FAIL IND", textcolor="gray", linecolor="green"];
bts -> bsc_l [label="RSL Dchan (SDCCH, SAPI0, DCCH) RF CHAN REL ACK"];
# connect BTS RTP with BSC-MGW RTP
--- [label="BSC configures RTP on BTS and both sides of MGW"];
bts <- bsc [label="RSL IPA CRCX", textcolor="blue", linecolor="blue"];
bts box bts [label="Bind to BTS-local RTP Port (1000)", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA CRCX ACK (BTS:1000)", textcolor="blue", linecolor="blue"];
bsc -> mgw [label="MGCP CRCX rtpbridge/2@mgw (BTS:1000)", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Bind to MGW-local RTP Port (2000)\nConnect to BTS:1000", textcolor="blue", linecolor="blue"];
bsc <- mgw [label="MGCP CRCX rtpbridge/2@mgw OK (MGW:2000)", textcolor="blue", linecolor="blue"];
bts <- bsc [label="IPA MDCX (MGW:2000)", textcolor="blue", linecolor="blue"];
bts box bts [label="Connect RTP socket to remote (MGW) RTP Port", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA MDCX ACK", textcolor="blue", linecolor="blue"];
bsc >> mgw [label="MGCP MDCX rtpbridge/2@mgw", textcolor="gray", linecolor="gray"];
bsc << mgw [label="MGCP MDCX rtpbridge/2@mgw OK", textcolor="gray", linecolor="gray"];
...;
--- [label="BSC finally can report successful TCH assignment"];
bsc -> m_sc [label="SCCP DT1 (BSSMAP ASSGN CMPL (3GPP AoIP MGW:3000))"];
m_sc box m_sc [label="Connect remote RTP to MGW addr from ASSGN CMPL"];
...;
mgw <-> m_sc [label="RTP Audio MGW:3000 MSC:4000", textcolor="blue", linecolor="blue"];
bts <-> mgw [label="RTP Audio BTS:1000 MGW:2000", textcolor="blue", linecolor="blue"];
ms <-> bts [label="Um Audio (bidirectional)", textcolor="blue", linecolor="blue"];
ms <-> m_sc [label="DTAP CC ALERTING"];
...;
--- [label="Further signalling in parallel with RTP (simplified)"];
ms <- m_sc [label="DTAP CC CONNECT"];
ms -> m_sc [label="DTAP CC CONNECT ACK"];
--- [label="Voice Call in Progress"];
...;
--- [label="B-end hangs up"];
ms <- m_sc [label="DTAP CC DISCONNET"];
ms <- m_sc [label="DTAP CC RELEASE"];
ms <- m_sc [label="DTAP CC RELEASE COMPL"];
...;
bsc <- m_sc [label="SCCP DT1 (BSSMAP CLEAR CMD)"];
bsc -> bsc [label="GSCON_EV_A_CLEAR_CMD", textcolor="red", linecolor="red"];
--- [label="BSC must release terrestrial resoures before reporting CLEAR COMPLETE"];
mgw <- bsc [label="MGCP DLCX rtpbridge/2@mgw", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Release MSC-facing local RTP port (3000)", textcolor="blue", linecolor="blue"];
mgw -> bsc [label="MGCP DLCX rtpbridge/2@mgw OK", textcolor="blue", linecolor="blue"];
mgw <- bsc [label="MGCP DLCX rtpbridge/2@mgw", textcolor="blue", linecolor="blue"];
mgw box mgw [label="Release BTS-facing local RTP port (2000)", textcolor="blue", linecolor="blue"];
mgw -> bsc [label="MGCP DLCX rtpbridge/2@mgw OK", textcolor="blue", linecolor="blue"];
bts <- bsc [label="IPA DLCX", textcolor="blue", linecolor="blue"];
bts box bts [label="Release BTS-local RTP port (1000)", textcolor="blue", linecolor="blue"];
bts -> bsc [label="IPA DLCX OK", textcolor="blue", linecolor="blue"];
bsc -> bsc [label="GSCON_EV_RSL_CLEAR_COMPL", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP DT1 (BSSMAP CLEAR COMPL)"];
bsc <- m_sc [label="SCCP RLSD"];
bsc -> bsc [label="GSCON_EV_A_DISC_IND", textcolor="red", linecolor="red"];
bsc -> m_sc [label="SCCP RLC"];
--- [label="BSC releases radio resources after CLEAR COMPLETE"];
bsc_l2 <= bsc [label="release_lchan(TCH)", textcolor="red", linecolor="red"];
bts <- bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) DATA REQ (RR CHANNEL RELEASE)", textcolor="green", linecolor="green"];
bsc_l2 box bsc_l2 [label="Start T3109"];
bts <- bsc_l2 [label="RSL Dchan (TCH) DEACTIVATE SACCH"];
ms <- bts [label="TCH: I (RR CHANNEL RELEASE)"];
ms -> bts [label="TCH: DISC (RR CHANNEL RELEASE)"];
bts -> bsc_l2 [label="RSL RLL (TCH, SAPI0, DCCH) REL IND", textcolor="green", linecolor="green"];
bsc_l2 => bsc [label="GSCON_EV_RLL_REL_IND", textcolor="red", linecolor="red"];
bsc_l2 box bsc_l2 [label="Stop T3109; Start T3111"];
# optional: Conn Fail?
bts <- bsc_l2 [label="RSL Dchan (TCH, SAPI0, DCCH) RF CHAN REL"];
bts -> bsc_l2 [label="RSL Dchan (TCH, SAPI0, DCCH) RF CHAN REL ACK"];
bsc_l2 box bsc_l2 [label="T3111 timeout: Channel can be used again"];
...;
}