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Content for
TS 29.079
Word version: 18.0.0
1…
4…
4
General
5
Common SDP Procedures
6
IMS-ALG procedures
7
UA Procedures
8
Subsequent SDP offer/answer transactions
A
Signalling flows
$
Change History
4
General
p. 8
5
Common SDP Procedures
p. 9
5.1
General
p. 9
5.2
Encapsulation of previous SDP information
p. 9
5.2.1
Media level information
p. 9
5.2.2
Session level information
p. 9
5.3
Determination of codec related SDP information associated to a previous realm instance
p. 10
5.4
Modifying codec related information
p. 11
5.4.1
Modifying the format list
p. 11
5.4.2
Modifying preferred configurations
p. 11
5.5
Additional handling for SDP answer with actual configuration
p. 12
5.6
Procedures specific to OMR attributes
p. 12
5.6.1
General
p. 12
5.6.2
instance-number
p. 12
5.6.3
Session and media checksum calculation
p. 13
5.7
Roaming architecture for voice over IMS with local breakout
|R11|
p. 13
5.8
II-NNI traversal scenario
|R12|
p. 13
6
IMS-ALG procedures
p. 13
6.1
IMS-ALG handling of initial SDP offer
p. 13
6.1.1
General
p. 13
6.1.2
Validating the received SDP offer
p. 14
6.1.3
Deciding whether to allocate a primary local MR and if any previous MR can be bypassed
p. 14
6.1.4
Bypassing previous MRs
p. 16
6.1.5
Bypassing no previous MRs
p. 16
6.1.6
Allocating a primary local MR
p. 16
6.1.7
Allocating no primary local MR
p. 17
6.1.8
Allocating secondary local MRs
p. 17
6.1.9
Forwarding SDP offer
p. 18
6.2
IMS-ALG handling of initial SDP answer
p. 18
6.2.1
General
p. 18
6.2.2
IMS-ALG bypasses an allocated transcoding MR
p. 18
6.2.3
IMS-ALG allocates a local transcoding MR when performing proactive transcoding without resource reservation
p. 19
6.2.4
IMS-ALG determines steps required to complete the handling of the SDP answer
p. 20
6.2.5
Receiving an unspecified connection address and a visited-realm instance
p. 20
6.2.6
Receiving an unspecified connection address and a secondary-realm instance
p. 21
6.2.7
Other handling when no primary local MR allocated
p. 21
6.2.8
Retaining a primary or secondary local MR
p. 21
6.2.9
Forwarding the SDP answer
p. 22
6.3
IMS-ALG OMR media resource operations
p. 23
6.3.1
General
p. 23
6.3.2
IMS-ALG operations
p. 23
6.4
Handling of connected IP realms
p. 23
7
UA Procedures
p. 24
7.1
UA sending an initial SDP offer
p. 24
7.2
UA receiving an initial SDP offer
p. 24
7.2.1
General
p. 24
7.2.2
Validating the incoming SDP offer
p. 24
7.2.3
UA may choose an alternate realm instance to bypass an upstream MR
p. 25
7.3
UA receiving an initial SDP answer
p. 25
7.3.1
General
p. 25
7.3.2
Receiving SDP answer with an unspecified connection address
p. 25
7.3.3
Receiving SDP answer with a valid connection address
p. 25
7.4
UA OMR media resource operations
p. 26
7.4.1
General
p. 26
7.4.2
UA operations
p. 26
7.5
Handling of connected IP realms
p. 26
8
Subsequent SDP offer/answer transactions
p. 26
8.1
General
p. 26
8.2
IMS-ALG and UA subsequent SDP offer procedures
p. 27
8.3
IMS-ALG and UA subsequent SDP answer procedures
p. 27
8.4
Handling media resources during a subsequent SDP offer/answer transaction
p. 28
A
Signalling flows
p. 29
A.1
Scope of signalling flows
p. 29
A.2
Introduction
p. 29
A.3
Media bypassing all IMS-ALGs
p. 30
A.3.1
General
p. 30
A.3.2
Message flow
p. 30
A.4
IMS-ALG allocates a local transcoding MR when performing proactive transcoding without resource reservation
p. 42
A.4.1
General
p. 42
A.4.2
Message flow
p. 42
A.5
IMS-ALG bypasses an allocated transcoding MR
p. 62
A.5.1
General
p. 62
A.5.2
Message flow
p. 62
A.6
Loopback routeing via an intermediate network
|R11|
p. 75
A.6.1
General
p. 75
A.6.2
Message flow
p. 76
$
Change History
p. 90