Name

AVP Code

Data Type

Vendor

BMSC-Address

3500

Address

3GPP

Specifies the IP address where the Broadcast/Multicast Service Center (BM-SC) expects to receive user data via the MB2-U interface. This AVP is primarily used in MBMS (Multimedia Broadcast Multicast Service) systems for handling data traffic directed to the BM-SC. The BMSC-Address facilitates the establishment of a unicast tunnel between the MBMS Gateway (MBMS-GW) and the BM-SC for transmitting broadcast/multicast data streams. 

BMSC-Port

3501

Unsigned32

3GPP

Specifies the port number on which the Broadcast/Multicast Service Center (BM-SC) expects to receive user data via the MB2-U interface. This AVP works in conjunction with the BMSC-Address AVP to establish a complete endpoint (IP address and port) for data delivery in MBMS (Multimedia Broadcast Multicast Service) systems. It defines the transport layer port for unicast tunnels created between the MBMS Gateway (MBMS-GW) and the BM-SC.

Common-Tunnel-Endpoint-Identifier

3524

OctetString

3GPP

Specifies the common tunnel endpoint identifier used by the MBMS Gateway (MBMS-GW) for the user plane. It acts as a unique identifier for the common tunnel endpoint associated with MBMS data delivery over the MB2-U interface, enabling data routing between the BM-SC (Broadcast/Multicast Service Center) and the UE (User Equipment).

FEC-Request

3525

OctetString

3GPP

Used by the GCS AS (Group Communication System Application Server) to request that the BM-SC (Broadcast/Multicast Service Center) applies Forward Error Correction (FEC) techniques, as specified in [RFC 6363]. This AVP includes an SDP (Session Description Protocol) description of the FEC framework configuration, providing parameters for encoding and decoding processes at the IP layer and higher protocol levels within the user plane data, according to [TS 26.346].

FEC-Result

3531

Unsigned32 (Bitmask)

3GPP

Representing a bitmask used to indicate the status of a Forward Error Correction (FEC) activation or execution request in the BM-SC (Broadcast/Multicast Service Center). Multiple bits may be set simultaneously to report errors or statuses in combination. This AVP is primarily used to provide detailed feedback on the result of the FEC-Request operation. Bitmask Values:

0 Success: Indicates the requested FEC activation was successful.

1 Trying: Indicates the requested FEC activation is ongoing, and the final result will be reported later.

2 Authorization Rejected: Indicates the requested FEC activation failed due to lack of authorization from the BM-SC.

3 Resources Exceeded: Indicates the BM-SC failed to provide sufficient resources for the FEC activation or execution.

4 Unknown Configuration: Indicates the BM-SC does not support the requested FEC configuration.

5 Invalid SDP: Indicates the requested FEC activation failed due to invalid SDP (Session Description Protocol) configuration.

6 System Error: Indicates the FEC activation or execution failed due to an internal system error in the BM-SC.

7 No Traffic: Indicates the FEC execution was terminated because no user plane traffic was detected for a prolonged period.

Local-M1-Information

3518

Grouped

3GPP

Used to provide information about the M1 interface between the eNB (Evolved Node B) and the MBMS GW (Multimedia Broadcast Multicast Service Gateway) for local MBMS (Multimedia Broadcast Multicast Services) data delivery. This AVP specifies the IP addresses and tunnel identifiers required for data delivery over the M1 interface, ensuring seamless multicast or broadcast data transmission. The AVP structure is defined as follows:

MBMS-eNB-IP-Multicast-Address (3519, Address): Contains the IPv4 multicast address of the eNB for receiving MBMS traffic.

MBMS-eNB-IPv6-Multicast-Address (3520, Address): Contains the IPv6 multicast address of the eNB for receiving MBMS traffic.

MBMS-GW-SSM-IP-Address (3521, Address): Contains the IPv4 Source-Specific Multicast (SSM) address of the MBMS GW.

MBMS-GW-SSM-IPv6-Address (3522, Address): Contains the IPv6 Source-Specific Multicast (SSM) address of the MBMS GW.

Common-Tunnel-Endpoint-Identifier (3524, OctetString): Identifies the common tunnel endpoint for the MBMS GW in the user plane.

Local-MB2-U-Information

3519

Grouped

3GPP

Used to provide MB2-U interface information for local MBMS data delivery. It specifies the IP address and port required for the BM-SC to receive user data over the MB2-U interface. This AVP facilitates communication between the BM-SC and other network elements, ensuring efficient handling of multicast or broadcast data delivery. The AVP structure is defined as follows:

BMSC-Address (3500, Address): Specifies the IPv4 or IPv6 address of the BM-SC for receiving user data. Supports dual-stack IPv4/IPv6.

BMSC-Port (3501, Unsigned32): Specifies the port number on which the BM-SC expects to receive user data over the MB2-U interface.

MB2U-Security

3517

Unsigned32

3GPP

Used to specify whether a security protocol is required or enabled for communication over the MB2-U interface. This AVP can be included in messages sent by the GCS AS (Group Communication System Application Server) to request security enforcement, or by the BM-SC to indicate the decided security policy. If this AVP is omitted, the default value is 0 (No Security).

Enumerated Values:

0 No Security: (Default). Specifies that no security protocol is required or enforced for the MB2-U interface. 

1 Security: Specifies that a security protocol is required or enforced for the MB2-U interface.

MBMS-Bearer-Event

3502

Unsigned32 (Bitmask)

3GPP

Utilizes a bitmask to represent MBMS bearer events. It indicates the status or outcome of MBMS bearer operations. Multiple bits may be set simultaneously, except for Bit 0 (Bearer Terminated) and Bit 1 (Bearer Activated), which are mutually exclusive. Bitmask Values:

0 Bearer Terminated: The MBMS bearer was terminated.

1 Bearer Activated: The MBMS bearer was activated successfully.

2 Userplane Event: A userplane event occurred, and additional results are specified in the Userplane-Protocol-Result AVP.

3 Bearer Activation Failure: The MBMS bearer failed to activate as scheduled in the MBMS-Start-Time.

MBMS-Bearer-Event-Diagnostic-Info

3533

Enumerated

3GPP

Provides diagnostic reasons for events related to MBMS bearer activation or termination. It helps to identify the specific cause of failure or termination in the MBMS service. Enumerated Values: 

0 TMGI-Expiry: Indicates that the MBMS bearer was terminated due to the expiry of TMGI (Temporary Mobile Group Identity).

1 MBMS-GW-Not-Establishment: Indicates that the MBMS bearer activation failed because the MBMS-GW could not be established.

2 SGmb-Transient-Path-Failure: Indicates that the MBMS bearer activation failed due to a transient path failure on the SGmb interface.

3 SGmb-Non-Transient-Path-Failure: Indicates that the MBMS bearer was terminated due to a non-transient path failure on the SGmb interface.

4 MBMS-GW-User-Plane-Failure: Indicates that the MBMS bearer was terminated because the MBMS-GW detected a user plane failure.

5 MBMS-GW-Permanent-Error: Indicates that the MBMS bearer was terminated due to a permanent error response from the MBMS-GW.

6 MBMS-GW-Transient-Error: Indicates that the MBMS bearer activation failed due to a transient error response from the MBMS-GW.

MBMS-Bearer-Event-Notification

3503

Grouped

3GPP

Used by the BM-SC to notify the GCS AS (Gateway Control Server Application Server) about events related to MBMS bearers. It provides detailed information about bearer events, diagnostics, and protocol results. The AVP structure is defined as follows:

TMGI (Temporary Mobile Group Identity) (OctetString): Identifies the specific MBMS session to which the event applies.

MBMS-Flow-Identifier (OctetString): Identifies the flow of the MBMS bearer session related to the event notification.

MBMS-Bearer-Event (Bitmask32): Indicates the event type related to the MBMS bearer, such as:

• 0 (Bearer Terminated): The MBMS bearer was terminated.

• 1 (Bearer Activated): The MBMS bearer was activated.

• 2 (Userplane Event): Reports a user plane event and provides results in Userplane-Protocol-Result AVP.

• 3 (Bearer Activation Failure): Indicates activation failure due to MBMS-Start-Time issues.

MBMS-Bearer-Event-Diagnostic-Info (Optional, Enumerated): Provides diagnostic reasons for the event, such as:

• 0 (TMGI-Expiry): Bearer expired due to TMGI timeout.

• 1 (MBMS-GW-Not-Establishment): Failure to establish MBMS-GW.

• 2 (SGmb-Transient-Path-Failure): Temporary path failure on SGmb interface.

• 3 (SGmb-Non-Transient-Path-Failure): Permanent path failure on SGmb interface.

• 4 (MBMS-GW-User-Plane-Failure): User plane failure detected by MBMS-GW.

• 5 (MBMS-GW-Permanent-Error): Permanent error response from MBMS-GW.

• 6 (MBMS-GW-Transient-Error): Temporary error response from MBMS-GW.

Userplane-Protocol-Result (Optional, Multiple Occurrences, Grouped): Provides results related to user plane protocol operations and error codes for detailed diagnostics.

MBMS-Bearer-Request

3504

Grouped

3GPP

Used by the GCS AS (Gateway Control Server Application Server) to activate, modify, or deactivate an MBMS bearer. It specifies the parameters required for bearer handling, including start/stop indications, service areas, QoS, and security configurations. The AVP structure is defined as follows:

MBMS-StartStop-Indication (Mandatory, Enumerated): Indicates whether the MBMS bearer is being activated, modified, or deactivated.

TMGI (Temporary Mobile Group Identity) (Optional, OctetString): Identifies the MBMS session associated with the bearer.

MBMS-Flow-Identifier (Optional, OctetString): Identifies the specific data flow associated with the MBMS bearer.

QoS-Information (Optional, Grouped): Defines the Quality of Service (QoS) parameters for the MBMS bearer, including:

• Maximum bit rate.

• Guaranteed bit rate.

• Priority level.

• Pre-emption vulnerability and capability.

MBMS-Service-Area (Optional, OctetString): Specifies the geographical area where the MBMS bearer should be active.

MBMS-Start-Time (Optional, Time): Indicates the start time for the MBMS bearer session.

MB2U-Security (Optional, Unsigned32): Specifies whether security protocols should be used for the MB2-U interface.

• 0 (No security) – No security protocol.

• 1 (Security) – Security protocol enabled.

MBMS-Cell-List (Optional, OctetString): Provides a list of cells where the MBMS bearer should be active.

Local-M1-Information (Optional, Grouped): Contains information about the M1 interface between the eNB (Evolved Node B) and the MBMS-GW (Gateway) for local MBMS delivery.

Local-MB2-U-Information (Optional, Grouped): Provides details for the MB2-U interface in local MBMS delivery, including IP addresses and ports.

FEC-Request (Optional, OctetString): Requests Forward Error Correction (FEC) configuration for improving data reliability.

ROHC-Request (Optional, Multiple Occurrences, OctetString): Requests the activation of Robust Header Compression (ROHC) for optimizing packet size.

ROHC-Max-CID (Optional, Unsigned32): Specifies the maximum number of context identifiers for ROHC.

MBMS-Bearer-Response

3505

Grouped

3GPP

Used by the BM-SC to notify the GCS AS (Gateway Control Server Application Server) about the result of an MBMS bearer request. It provides information about activation, modification, or deactivation status, as well as the session parameters such as addresses, ports, and security configurations. The AVP structure is defined as follows:

TMGI (Temporary Mobile Group Identity) (Optional, OctetString): Identifies the MBMS session associated with the bearer response.

MBMS-Flow-Identifier (Optional, OctetString): Identifies the specific flow related to the MBMS bearer.

MBMS-Session-Duration (Optional, Unsigned32): Specifies the duration of the MBMS session in seconds.

MBMS-Bearer-Result (Optional, Enumerated): Provides the result of the bearer request, indicating whether it was successful or failed.

BMSC-Address (Optional, up to 2 occurrences, Address): Specifies the BM-SC IP address (IPv4 or IPv6) where user data is received via the MB2-U interface.

BMSC-Port (Optional, Unsigned32): Specifies the port number on which the BM-SC receives user data via the MB2-U interface.

MB2U-Security (Optional, Unsigned32): Defines whether security protocols are used on the MB2-U interface.

• 0 (No security) – No security protocols used.

• 1 (Security) – Security protocols enabled.

Radio-Frequency (Optional, Multiple Occurrences, Unsigned32): Specifies the radio frequency used for delivering MBMS services.

Userplane-Protocol-Result (Optional, Multiple Occurrences, Grouped): Provides the result of user plane protocol configuration, including whether protocol setup was successful or failed due to errors.

MBMS-Bearer-Result

3506

Bitmask32

3GPP

Used to convey the result status of an MBMS bearer request. It provides detailed information about whether the activation, modification, or deactivation of the bearer was successful or failed, including specific reasons for failure. Multiple bits can be set simultaneously, especially to indicate ongoing processes combined with partial success.

Enumerated Values:

SUCCESS (Bit 0): Indicates the bearer operation (activation, modification, or deactivation) was successful. When combined with Bit 13, it means the request was handled, but activation is still ongoing.

AUTHORIZATION_REJECTED (Bit 1): Indicates the BM-SC rejected the operation due to authorization failure.

RESOURCES_EXCEEDED (Bit 2): Indicates the BM-SC could not provide sufficient resources to complete the operation.

UNKNOWN_TMGI (Bit 3): The requested TMGI (Temporary Mobile Group Identity) is either unknown or has expired.

TMGI_NOT_IN_USE (Bit 4): The requested TMGI is not associated with any active MBMS bearer.

OVERLAPPING_MBMS_SERVICE_AREA (Bit 5): The requested service area overlaps with an existing service area for the TMGI, causing a modification failure.

UNKNOWN_FLOW_IDENTIFIER (Bit 6): The requested flow identifier is unknown to the BM-SC.

QOS_AUTHORIZATION_REJECTED (Bit 7): The requested QoS parameters were not authorized by the BM-SC.

UNKNOWN_MBMS_SERVICE_AREA (Bit 8): The requested MBMS service area is unknown to the BM-SC.

MBMS_SERVICE_AREA_AUTHORIZATION_REJECTED (Bit 9): The requested service area was not authorized by the BM-SC.

MBMS_START_TIME (Bit 10): The provided start time for the MBMS session is invalid or inappropriate.

INVALID_AVP_COMBINATION (Bit 11): The AVP combination in the MBMS-Bearer-Request is invalid or incomplete for the given operation.

SYSTEM_ERROR (Bit 12): Internal system error at the BM-SC caused the operation to fail.

ACTIVATION_ONGOING (Bit 13): Indicates that the bearer activation process is ongoing and not yet complete. May be set with Bit 0 to confirm partial success.

MBMS-eNB-IP-Multicast-Address

3520

Address

3GPP

Used to store the IPv4 multicast destination address on the M1 transport plane. This address is utilized by the MBMS-GW (Multimedia Broadcast Multicast Service Gateway) for IP multicast encapsulation of user plane IP multicast datagrams.

MBMS-eNB-IPv6-Multicast-Address

3521

Address

3GPP

Specifies the IPv6 multicast destination prefix on the M1 transport plane. This prefix is used by the MBMS-GW (Multimedia Broadcast Multicast Service Gateway) for IP multicast encapsulation of user plane IP multicast datagrams.

MBMS-GW-SSM-IP-Address

3522

Address

3GPP

Specifies the IPv4 address of the MBMS-GW (Multimedia Broadcast Multicast Service Gateway) used for Source Specific Multicasting (SSM). This AVP is applicable for IPv4-only or dual-stack MBMS-GW configurations and is a critical parameter for establishing multicast group communications.

MBMS-GW-SSM-IPv6-Address

3523

Address

3GPP

Specifies the IPv6 address of the MBMS-GW (Multimedia Broadcast Multicast Service Gateway) used for Source Specific Multicasting (SSM). This AVP is utilized in dual-stack MBMS-GW configurations, enabling IPv6 multicast traffic delivery for broadcast and multicast services.

MBMS-Start-Time

3507

Time

3GPP

Specifies the requested start time for the allocation of an MBMS bearer. This AVP is primarily used in scenarios where broadcast or multicast services require a predefined activation schedule.

Radio-Frequency

3508

Unsigned32

3GPP

Used by the BM-SC to specify radio frequencies as part of the MBMS (Multimedia Broadcast Multicast Service) bearer configuration information sent to the GCS AS (Group Communication Service Application Server). Aligns with the [TS 26.346] standard for MBMS configuration, ensuring compliance with radiofrequency definitions in the infoBinding element.

ROHC-Full-Header-Periodicity

3527

Float32

3GPP

Specifies the target periodicity (in seconds) for sending full header packets in ROHC (Robust Header Compression) as defined in [RFC 5795] and [RFC 3095]. ROHC is used to compress protocol headers in IP-based communication to reduce overhead and improve efficiency for low-bandwidth or high-latency networks such as mobile or multicast environments.

ROHC-Max-CID

3532

Unsigned32

3GPP

Specifies the maximum Context Identifier (CID) parameter for the ROHC (Robust Header Compression) compressor, as defined in [RFC 5795] and [RFC 3095]. Context Identifiers (CIDs) are used in ROHC to distinguish between multiple compressed streams. Each context maintains the state information for header compression and decompression.

The ROHC-Max-CID AVP also determines whether the LARGE_CIDS parameter is used based on the MAX_CID value:

LARGE_CIDS = TRUE if MAX_CID > 15: uses large CID representation.

LARGE_CIDS = FALSE if MAX_CID ≤ 15: uses short CID representation.

ROHC-Profile

3528

Unsigned32

3GPP

Specifies the applicable ROHC (Robust Header Compression) profile used for compressing IP, UDP, and RTP headers, as defined in [RFC 5795]. This AVP identifies the compression profile to be applied, enabling optimized handling of header fields based on protocol type. The value of this AVP is restricted to the following profiles:

0x0001 (RTP/UDP/IP Profile): compresses RTP (Real-Time Protocol) headers along with UDP/IP headers for applications like VoIP and video streaming.

0x0002 (UDP/IP Profile): compresses only UDP/IP headers for scenarios where RTP is not used, such as general UDP data streams.

ROHC-Request

3526

Grouped

3GPP

Used by the GCS AS (Generic Control Server Application) to request that the BM-SC (Broadcast Multicast Service Center) applies ROHC (Robust Header Compression) as specified in [RFC 5795] and [RFC 3095] for specific downlink media streams. This AVP describes the target data streams and configuration parameters required to enable header compression at the IP layer and higher protocol layers in user plane data transmission. The AVP structure is defined as follows:

Flow-Description (Required, Enumerated): Specifies the downlink media streams to which ROHC should be applied. 1 or more instances required.

ROHC-Full-Header-Periodicity (Optional, Float32 (seconds)): Specifies the target periodicity for sending full header packets during ROHC operation.

ROHC-Profile (Required, Unsigned32): Specifies the ROHC profile to be applied for compression. Defined Values:

• 0x0001 – RTP/UDP/IP Profile for VoIP and multimedia streaming.

• 0x0002 – UDP/IP Profile for general data streams.

ROHC-Result

3530

Unsigned32 (Bitmask)

3GPP

Represents a bitmask that indicates the status or result of a ROHC (Robust Header Compression) activation, modification, or execution attempt. This AVP provides diagnostic feedback to the GCS AS (Generic Control Server Application) from the BM-SC, specifying whether the requested ROHC operation was successful, is ongoing, or failed due to specific errors. Multiple bits may be set simultaneously to reflect combined statuses (e.g., partial success with pending final results). Bitmask Definitions:

0 Success: The requested ROHC activation was successful.

1 Trying: The ROHC activation is ongoing. The final result will be reported later.

2 Authorization Rejected: The BM-SC did not authorize the requested ROHC activation.

3 Resources Exceeded: The BM-SC could not allocate sufficient resources to execute the requested ROHC.

4 Unknown Profile: The BM-SC does not support the requested ROHC profile.

5 System Error: The ROHC operation failed due to an internal error in the BM-SC.

6 No Traffic: The ROHC execution was terminated due to no user plane traffic detected for a while.

TMGI-Allocation-Request

3509

Grouped

3GPP

Used by the GCS AS (Generic Control Server Application) to request either allocation of new TMGIs (Temporary Mobile Group Identifiers), or Timer refresh for existing TMGIs.

It allows the GCS AS to manage TMGIs for MBMS sessions, ensuring proper identification and session management across the network. The AVP structure is defined as follows:

TMGI-Number (Mandatory, Unsigned32): Specifies the number of new TMGIs being requested. Excludes TMGIs that are part of timer refresh requests.

TMGI (Optional, Repeated, OctetString): Lists the TMGIs for which a timer refresh is requested.

Allows additional AVPs if required by custom implementations or future extensions.

TMGI-Allocation-Response

3510

Grouped

3GPP

Used by the BM-SC to notify the GCS AS (Generic Control Server Application) about the result of a TMGI (Temporary Mobile Group Identity) allocation or timer refresh request. It supports full success, partial success, and failure scenarios, providing detailed feedback on the allocation or refresh operation. The AVP structure is defined as follows:

TMGI (Optional, Repeated, OctetString): Lists all successfully allocated or refreshed TMGIs. Can include multiple entries for batch processing.

MBMS-Session-Duration (Optional, Unsigned32 (seconds)): Indicates the common expiration time for the successfully allocated or refreshed TMGIs. Helps synchronize session lifetimes.

TMGI-Allocation-Result (Optional, Bitmask32): Provides status and reasons for partial success or failure scenarios. Combines success and failure codes for clarity.

Allows for future extensions or custom information.

TMGI-Allocation-Result

3511

Unsigned32 (Bitmask)

3GPP

Used by the BM-SC to report the result of a TMGI (Temporary Mobile Group Identity) allocation or timer refresh request. It can convey multiple error conditions in combination, providing detailed feedback for partial failures or success scenarios.

Bitmask Values

0 Success: The TMGI allocation request was successful.

1 Authorization rejected: Allocation failed because authorization was denied by the BM-SC.

2 Resources exceeded: Allocation failed due to insufficient resources at the BM-SC.

3 Unknown TMGI: Refresh failed because the requested TMGI was unknown (e.g., expired).

4 Too many TMGIs requested: Allocation failed because the maximum number of allowed TMGIs for the GCS AS exceeded.

5 System error: Allocation failed due to an internal system error at the BM-SC.

TMGI-Deallocation-Request

3512

Grouped

3GPP

Used by the GCS AS (Group Communication Service Application Server) to request the deallocation of TMGIs (Temporary Mobile Group Identities) previously allocated for MBMS sessions. This AVP facilitates the release of resources associated with specified TMGIs, ensuring that expired or unused group identifiers can be reclaimed and reassigned as needed. The AVP structure is defined as follows:

TMGI (OctetString): Identifies the group session to be deallocated. Supports multiple instances for batch deallocation.

TMGI-Deallocation-Response

3513

Grouped

3GPP

Used by the BM-SC to inform the GCS AS (Group Communication Service Application Server) about the result of a TMGI (Temporary Mobile Group Identity) deallocation request. It provides feedback on whether the deallocation was successful or unsuccessful, including the reason for failure if applicable. The AVP structure is defined as follows:

TMGI (OctetString): Identifies the TMGI related to the deallocation operation. Multiple instances supported for batch results.

TMGI-Deallocation-Result (Optional, Enumerated/Bitmask (specific errors)): Indicates the result of the deallocation (success or failure reasons).

TMGI-Deallocation-Result

3514

Unsigned32 (Bitmask)

3GPP

Reports the outcome of a TMGI (Temporary Mobile Group Identity) deallocation request. It provides granular feedback on whether the deallocation was successful or failed, specifying the reason for failure using bitmask values.

Each bit represents a specific result or error condition. Multiple bits may be set simultaneously to indicate combined errors. Bitmask Values: 

0 Success: The requested TMGI deallocation was successful.

1 Authorization Rejected: The deallocation request was rejected because the BM-SC (Broadcast Multicast Service Center) did not authorize it.

2 Unknown TMGI: The BM-SC could not recognize the TMGI, possibly because it had already expired.

3 System Error: An internal error in the BM-SC caused the deallocation failure.

TMGI-Expiry

3515

Grouped

3GPP

Used by the BM-SC to notify the GCS AS (Group Communication Service Application Server) about the expiry of TMGIs (Temporary Mobile Group Identities). It provides a list of expired TMGIs, enabling the GCS AS to handle expired resources effectively and take appropriate actions, such as resource cleanup or reallocation requests. The AVP structure is defined as follows:

TMGI (Mandatory, Multiple Instances): Represents the expired TMGIs in the notification.

Allows additional AVPs for future extensions.

TMGI-Number

3516

Unsigned32

3GPP

Used to indicate the number of requested TMGIs (Temporary Mobile Group Identities) in a TMGI Allocation Request. It specifies the count of new TMGIs being requested, excluding any TMGIs for which only a timer refresh is being requested.

Userplane-Protocol-Result

3529

Grouped

3GPP

Used by the BM-SC to report the results of the activation or failures during the execution of user plane protocols. It provides feedback on protocol-specific outcomes for downlink media streams within the User Plane Data context, as defined in [TS 26.346]. The AVP structure is defined as follows:

Flow-Description (Grouped): Describes the downlink media streams for which the protocol results apply. Absence implies results apply to all media streams.

ROHC-Result (Enumerated): Reports the result of ROHC (Robust Header Compression) activation or failures.

FEC-Result (Enumerated): Reports the result of FEC (Forward Error Correction) activation or failures.

Allows additional AVPs to be included for extensibility.