Call Hold SS » History » Version 2
laforge, 06/03/2018 10:35 PM
1 | 1 | laforge | h1. Call Hold SS |
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3 | Call Hold (HOLD) is specified together with Call Waiting (CW). |
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5 | h2. Relevant Specifications |
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7 | 2 | laforge | * "3GPP TS 22.083: Call Waiting (CW) and Call Hold (HOLD) supplementary service; Stage 1":http://www.etsi.org/deliver/etsi_ts/122000_122099/122083/14.00.00_60/ts_122083v140000p.pdf |
8 | ** high-level description + definition |
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9 | 1 | laforge | * "3GPP TS 23.083: Call Waiting (CW) and Call Hold (HOLD) supplementary service; Stage 2":http://www.etsi.org/deliver/etsi_ts/123000_123099/123083/14.00.00_60/ts_123083v140000p.pdf |
10 | ** contains SDL state diagrams for VLR and MSC |
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11 | 2 | laforge | * "3GPP TS 24.010: Supplementary services specification":http://www.etsi.org/deliver/etsi_ts/124000_124099/124010/14.00.00_60/ts_124010v140000p.pdf |
12 | * "3GPP TS 24.080: supplementary services specification; Formats and coding":http://www.etsi.org/deliver/etsi_ts/124000_124099/124080/14.01.00_60/ts_124080v140100p.pdf |
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13 | 1 | laforge | * "3GPP TS 24.083: Call Waiting (CW) and Call Hold (HOLD) supplementary service; Stage 3":http://www.etsi.org/deliver/etsi_ts/124000_124099/124083/14.00.00_60/ts_124083v140000p.pdf |
14 | ** contains information on signaling on L3 interface between MS and MSC |
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17 | h2. Notes |
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19 | * the HOLD state is not a state in the 24.007/24.008 call control state machine, but an auxiliary state machine: |
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20 | ** *Idle* before/after any HOLD or after HOLD REJECT. |
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21 | ** *Hold request* HOLD sent but no response yet |
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22 | ** *Call Held* after successful HOLD operation |
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23 | ** *Retrieve request* RETRIEVE sent but no response yet |
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26 | h3. notification of other party |
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28 | The other party is notified if SS-screening != 0: |
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29 | ** Facility/Invoke/NotifySS/HOLD |
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31 | h3. HOLD activation |
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33 | * MS sends HOLD |
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34 | * MSC responds with HOLD ACK in successful case |
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35 | * MSC responds with HOLD REJECT in error case (#29: rejected, #50: not subscribed, #69: not implemented, ...) |
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37 | h3. RETRIEVE activation |
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39 | * MS sends RETRIEVE |
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40 | * MSC responds with RETRIEVE ACK in successful case |
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41 | * MSC responds with RETRIEVE REJECT in unsuccessful case |
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43 | h3. altenating between calls |
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45 | The HOLD/RETRIEVE messages contain the regular CC transaction identifer, which is used to differentiate different calls. You can put one call on hold and subsequently retrieve another. |