| Protocol | lte-rrc | Network | lte |
|---|---|---|---|
| Spec | 3GPP TS 36.331 | Spec Section | 5.6.25, 6.2.2 |
| Direction | eNodeB -> UE | Message Type | Segmented Dedicated Control |
| Full message name | LTE RRC DL Dedicated Message Segment-r16 |
|---|---|
| Protocol | LTE-RRC |
| Technology | LTE |
| Direction | eNodeB -> UE |
| Interface | Uu |
| Signaling bearer / channel | SRB1 / SRB2 / DL-DCCH |
| Typical trigger | A downlink dedicated LTE RRC payload is too large for a single message unit and must be segmented. |
| Main purpose | Lets the network deliver a large protected dedicated RRC payload over multiple downlink segments while preserving the ordering needed for reassembly. |
| Main specification | 3GPP TS 36.331, 5.6.25, 6.2.2 |
| Release added | Release 16 |
| Procedures where used | DL Message Segment Transfer, Segmented Dedicated RRC Delivery |
Downlink LTE RRC segmentation container used when a dedicated LTE RRC message is split across multiple fragments.
Lets the network deliver a large protected dedicated RRC payload over multiple downlink segments while preserving the ordering needed for reassembly.
DL Dedicated Message Segment-r16 is the LTE wrapper used when a large downlink dedicated RRC message is split into pieces.
Call flow position: Fragment container used during delivery of a large dedicated LTE RRC payload.
Typical state: UE is in connected mode.
Preconditions:
Next likely message: Further DL segments or reassembled final handling
Call flow position: Segmentation branch used when a large connected-mode reconfiguration-related payload must be split.
Typical state: UE remains in connected mode.
Preconditions:
Next likely message: Final reassembly and later procedure continuation
Previous message(s): Large dedicated LTE RRC payload becomes segmented
Next message(s): Later DL segments, Reassembled dedicated message handling
Security context: Sent as protected connected-mode signaling.
DLDedicatedMessageSegment-r16 ::= SEQUENCE {
criticalExtensions CHOICE {
c1 CHOICE {
dlDedicatedMessageSegment-r16 DLDedicatedMessageSegment-r16-IEs,
spare3 NULL,
spare2 NULL,
spare1 NULL
},
criticalExtensionsFuture SEQUENCE {}
}
}
DLDedicatedMessageSegment-r16-IEs ::= SEQUENCE {
segmentNumber-r16 INTEGER,
rrc-MessageSegmentContainer-r16 OCTET STRING
}
The outer structure is simple. The main issue is whether all segments arrive and reassemble correctly.
DL-DCCH-Message
message c1 : dlDedicatedMessageSegment-r16 : {
criticalExtensions c1 : dlDedicatedMessageSegment-r16 : {
segmentNumber-r16 1,
rrc-MessageSegmentContainer-r16 '8A2301'H
}
}
| IE | Required | Description |
|---|---|---|
segmentNumber-r16 | Yes | Identifies the downlink segment sequence. |
rrc-MessageSegmentContainer-r16 | Yes | Carries the fragment of the dedicated RRC payload. |
segmentNumber-r16Identifies the downlink segment sequence.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
rrc-MessageSegmentContainer-r16Carries the fragment of the dedicated RRC payload.
Presence: Required
In practice: In practice, compare this field with the original request and with any later release-dependent optional fields so you can see whether the network accepted the same service model the UE asked for.
Likely cause: One or more downlink segments may be missing or reassembly may have failed.
What to inspect: Check segment continuity and the later absence of the expected full-message outcome.
Next step: Compare the segmented case against a known-good full delivery.
It is the LTE RRC downlink segment container used when a dedicated message is too large to send as one unit.
Decode this message with the 3GPP Decoder, inspect the related message database, or open the matching call flow to see where this signaling step fits in the full procedure.