tems investigation call event definitions

TEMS Investigation Call Event Definitions

Technical Reference

TEMS Investigation Call Event Definitions 2009-05-14

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2009-05-14 TEMS Investigation Call Event Definitions

TMS-06:000205 Uen Rev B

Contents

1. Introduction ................................................................1

2. Description of Call Events.........................................12.1. Event State Machine...............................................................12.2. Description of Call Events.......................................................3

2.2.1. Call Initialization ......................................................................................32.2.2. Call Attempt ............................................................................................32.2.3. Call Attempt Retry...................................................................................32.2.4. Call Setup ...............................................................................................42.2.5. Call Established ......................................................................................42.2.6. Call End ..................................................................................................42.2.7. Blocked Call ............................................................................................52.2.8. Dropped Call ...........................................................................................5


TMS-06:000205 Uen Rev B 1(5)

1. Introduction

This document provides an in-depth description of how call events are generated in TEMS Investigation. By “calls” are meant voice calls as well as video calls (the latter in WCDMA only).

The document should be regarded as supplementary to the account of the call events in the user documentation (“Information Elements and Events” volume).

2. Description of Call Events

2.1. Event State Machine

When explaining the generation of call events in TEMS Investigation, it is helpful to refer to the state machine depicted below.


2(5) Public

(0) NULL

States 4, 7, 8, 9, 10

(11) DISCONNECTREQUEST

(10) ACTIVE

(4) CALLDELIVERED

(1) CALL INIT Setup (UL)

Alerting

Connect

(6) CALLPRESENT

(9) MT CALLCONFIRMED

Disconnect (UL)

Disconnect (DL)(12) DISCONNECTINDICATION

Release

Setup (DL)

Call Confirmed

(7) CALLRECEIVED

(8) CONNECTREQUEST

Alerting

ConnectConnect Acknowledge

States1,4,6,7,8,9

Release orRelease Complete

Release

Connect

Relea

se

(W1) RRC ConnectionRequested

(W2) RRC ConnectionSetup Received

(W3) RRC ConnectionSetup Complete Received

(G1) GSM Channel Requested

(G2) GSM Channel Assigned

Cha

nnel

Req

uest

RR

C C

onne

ctio

n R

eque

st

Channel RequestRRC ConnectionRequest

Channel R

elease orIm

mediate A

ssignment R

eject

RRC Connection Setup

RR

C C

onnection Reject

RRC Connection Setup Complete

Immediate Assignment

Setup (UL)Setup (DL) Setup (DL)

Setup (UL)

Connect

The state machine covers both WCDMA and GSM. The top left part shows the WCDMA service setup, while the top right part shows the service setup in GSM. Note that these setup procedures are generic and not unique to the speech service. MO calls are represented by states 1-4-10; MT calls are represented by states 6-9-7-8-10. The central part of the diagram, including states 11 and 12, is concerned with the handling of call disconnects.


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Each state has a tag “[X]n” where [X] is an (optional) letter and n is a number. States without a letter are valid in both GSM and WCDMA; states with “G” in front of the number are valid only for GSM; states with “W” in front of the number are valid only for WCDMA.

Layer 3 and CC messages are represented by arrows. For certain messages the direction (UL or DL) is indicated. Please note that the depiction of the message traffic and state transitions is a simplified one, with only the most important mechanisms included. Note in particular that a transition to state NULL can take place from any state following one of the events Blocked Call or Dropped Call; such state transitions are not shown in the diagram.

2.2. Description of Call Events

2.2.1. Call Initialization

This event is generated only when the call is initiated by a command sequence and only for mobile-originated (MO) calls. The event is triggered by a phone mode report (i.e. not by a Layer 3 message) which in turn is generated at the time the “yes” (or “send”) key is pressed.

2.2.2. Call Attempt

This event is generated in the following circumstances:

1. (GSM) Channel Request message with establishment cause “Speech” received in state NULL.

2. (WCDMA) RRC Connection Request message with establishment cause “Speech” received in state NULL.

3. Setup message received in state NULL. This can occur when a channel has been set up for a service other than speech and a CM Service Request has been received to change the reason for the channel setup. (The CM Service Request message itself does not have a cause value indicating whether speech is being requested, so it is not possible to have the Call Attempt event triggered by CM Service Request.)

2.2.3. Call Attempt Retry


1. (GSM) Channel Request message with establishment cause “Speech” received in state GSM Channel Requested.

2. (WCDMA) RRC Connection Request message with establishment cause “Speech” received in state RRC Connection Requested.


4(5) Public

2.2.4. Call Setup


3. Connect message received in state Call Init or in state MT Call Confirmed.

4. Alerting message received in state Call Init or state MT Call Confirmed.

Extra Information

Call direction: “MO call” or “MT call”.

Call setup time in ms, measured from Call Attempt, i.e. the first call attempt; this is not included if Call Attempt was triggered by the Setup message (see section 2.2.2, step 2).

User setup time in ms, measured from Call Initialization (thus more accurately reflecting the user-perceived setup time). Included only if the Call Initialization event has been previously generated, i.e. for MO calls in a command sequence.

2.2.5. Call Established

This event is generated when entering state Active following the message Connect (MO call) or Connect Acknowledge (MT call).

2.2.6. Call End


1. Release message sent or received by phone, causing return to state NULL without any of the events Blocked Call or Dropped Call having been generated during the call.

2. Channel Release message received in state GSM Channel Assigned. The following event information is then appended: “Not a call, procedure completed with a SDCCH” (cf. below).

Extra Information

1. Call end cause, one of the following strings:

MS initiated release NW initiated release User busy Not a call, procedure completed with a SDCCH Technical drop: Release Missing

2. Call duration in ms, indicating the time elapsing between the event Call Established and the message Disconnect or (if, exceptionally, no Disconnect is received) the message Release.


TMS-06:000205 Uen Rev B 5(5)

2.2.7. Blocked Call

This event is generated if the call is abnormally ended before the event Call Established is generated.

Extra Information

1. Block type, one of the following:

No Immediate Assignment No Traffic Channel Assignment No Alerting or Connect No Connect No Call Confirmed No Connect Acknowledge No RRC Connection Setup No RRC Connection Setup Complete RRC Connection Reject Abnormal RRC Connection Release No Setup No Radio Bearer Setup Complete N-300 and T-300 expiry

2. “CC Cause: <str>”, where <str> is a string. Included if the message that generated the event included CC cause.

3. "RR Cause: <str>", where <str> is a string. Included if the message that generated the event included RR cause.

4. Call time in ms, indicating the time since the event Call Initialization.

2.2.8. Dropped Call

This event is generated if the call is abnormally ended after the event Call Established.

Extra Information

1. Drop type, one of the following:

Abnormal network Abnormal RRC Connection Release No service

2. “Cause: <str>”, where <str> is a string describing the cause of the drop.

3. “CC Cause: <str>”, where <str> is a string. Included if the message that generated the event included CC cause.

4. Call duration in ms, indicating the time since the event Call Established.

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