Content for TS 23.172 Word version: 18.0.0

1… 4… 4.2.2… 4.2.3 4.2.4 4.2.5… 4.2.5.2 4.3… 4.3.2… 4.3.3… 4.3.3.1.3 4.3.3.1.4 4.3.3.1a… 4.3.4 4.3.5… 4.3.5.2 4.3.6…

4.2.3 Mobile originating side - completion of call setup
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4.2.3 Mobile originating side - completion of call setup p. 12

If the preferred mode, that is the first BC-IE indicated by the originating UE, was selected as the result of negotiations, the call shall be set up normally towards the originating UE.

If the negotiation resulted in a change of the selected mode, i.e. the call was set up as "multimedia first" and changed during the negotiation to a speech call, or vice-versa, because of either fallback or change of selected mode and the Call Proceeding message has been sent then an In-Call Modification procedure (see clause 5.3.4.3 of TS 24.008) shall be initiated towards the originating UE after the call control entity has entered the active state, i.e. the CONNECT message has been sent.

Copy of original 3GPP image for 3GPP TS 23.172, Fig. 4.10: Preferred mode selected

Figure 4.10: Preferred mode selected
(⇒ copy of original 3GPP image)

Copy of original 3GPP image for 3GPP TS 23.172, Fig. 4.11: Less preferred mode selected, accepted

Figure 4.11: Less preferred mode selected, accepted
(⇒ copy of original 3GPP image)

Copy of original 3GPP image for 3GPP TS 23.172, Fig. 4.12: Less preferred mode selected, rejected

Figure 4.12: Less preferred mode selected, rejected
(⇒ copy of original 3GPP image)

If the Call Proceeding message is delayed until response from the terminating side then it may include one or both BCs either in the order requested from the Originating UE or the order of the BCs may be reversed, depending on the result from the negotiation or (single BC) due to fallback. See Figure 4.12a.

Copy of original 3GPP image for 3GPP TS 23.172, Fig. 4.12a: Call Proceeding Delayed

Figure 4.12a: Call Proceeding Delayed
(⇒ copy of original 3GPP image)