LTE Deactivate EPS Bearer Context Request

Message Fact Sheet

Protocol	nas	Network	lte
Spec	3GPP TS 24.301	Spec Section	6.4.4.2, 8.3.12
Direction	MME to UE	Message Type	ESM signaling

Full message name	LTE Deactivate EPS Bearer Context Request
Protocol	NAS
Technology	LTE
Direction	MME to UE
Interface	N1 over LTE access / S1-MME control path
Signaling bearer / channel	NAS signaling / Commonly carried in downlink NAS transport after service policy changes, PDN cleanup, bearer reconfiguration, or session release handling.
Typical trigger	Sent when the network wants the UE to release an existing default or dedicated EPS bearer because the session branch is ending, changing, or being cleaned up.
Main purpose	Carries the bearer identity and deactivation reason so the UE can remove the requested bearer context and return the matching completion message.
Main specification	3GPP TS 24.301, 6.4.4.2, 8.3.12
Release added	Release 8
Procedures where used	EPS Bearer Context Deactivation Procedure, Dedicated Bearer Release, PDN Connection Cleanup, Bearer Policy Reconfiguration
Related timers	T3495
Related cause values	ESM cause

What is LTE Deactivate EPS Bearer Context Request in simple terms?

Deactivate EPS Bearer Context Request is the EPS session-management message the network sends when it wants the UE to release a default or dedicated bearer context that is no longer needed.

Carries the bearer identity and deactivation reason so the UE can remove the requested bearer context and return the matching completion message.

Why this message matters

Deactivate EPS Bearer Context Request is the network telling the UE to release a bearer that was active earlier.

Where this message appears in the call flow

Dedicated bearer release after service change

LTE dedicated bearer release flow showing Deactivate EPS Bearer Context Request followed by UE completion — When a service-specific bearer is no longer needed, Deactivate EPS Bearer Context Request starts the release branch for that dedicated bearer.

Call flow position: Network-initiated bearer release message sent when a previously active dedicated bearer is no longer needed for the service flow.

Typical state: The network is cleaning up a service-specific bearer while keeping the wider PDN connection active.

Preconditions:

The dedicated bearer was active earlier.
The network decided the service-specific bearer should now be released.

Next likely message: Deactivate EPS Bearer Context Accept

PDN connection cleanup or release

LTE PDN cleanup flow showing Deactivate EPS Bearer Context Request during bearer release handling — During PDN cleanup, Deactivate EPS Bearer Context Request tells the UE which active bearer should now be removed.

Call flow position: Bearer deactivation message sent when the network is cleaning up one or more bearers as part of PDN release handling.

Typical state: The bearer branch is moving from active service toward release and resource cleanup.

Preconditions:

The relevant bearer context is still active.
The network has decided that the bearer should be removed.

Next likely message: Deactivate EPS Bearer Context Accept

Bearer reconfiguration or policy update

LTE bearer policy update flow showing Deactivate EPS Bearer Context Request after a reconfiguration decision — When policy or service handling changes, Deactivate EPS Bearer Context Request removes the bearer that no longer fits the updated branch.

Call flow position: Network-driven bearer release used when policy, QoS handling, or service layout has changed and an existing bearer must be removed.

Typical state: The bearer layout is changing and the network is asking the UE to release the selected EPS bearer context.

Preconditions:

An active bearer exists for the targeted service branch.
The network has determined that the current bearer should be deactivated.

Next likely message: Deactivate EPS Bearer Context Accept

Call flow position

Previous message(s): Activate Default EPS Bearer Context Accept, Activate Dedicated EPS Bearer Context Accept, Service Request

Next message(s): Deactivate EPS Bearer Context Accept, Bearer release completion, PDN service cleanup

Message direction and transport

Sender and receiver: MME to UE

Interface: N1 over LTE access / S1-MME control path

Domain: Core-side EPS session management signaling used to release a previously active EPS bearer context.

Signaling bearer: NAS signaling

Logical channel: Commonly carried in downlink NAS transport after service policy changes, PDN cleanup, bearer reconfiguration, or session release handling.

Transport / encapsulation: EPS NAS ESM message sent by the MME and delivered to the UE through the eNodeB as part of bearer deactivation.

Security context: Deactivate EPS Bearer Context Request appears after EPS registration and bearer setup are already active, so it is normally seen in protected NAS continuation.

Message Structure Overview

Deactivate EPS Bearer Context Request is an EPS session-management message rather than an ASN.1 LTE RRC structure.
The practical reading path starts with which bearer is being released and whether it is a default or dedicated bearer.
In real traces, this message explains why the network is tearing down a bearer that was active earlier.

ASN.1 Message Syntax for LTE Deactivate EPS Bearer Context Request

Deactivate EPS Bearer Context Request
  EPS bearer identity
  ESM cause                            OPTIONAL
  Protocol configuration options       OPTIONAL

How to read this message syntax

Deactivate EPS Bearer Context Request is a NAS layer-3 ESM message, not an ASN.1 LTE RRC message. Read it first from the bearer identity, then from the broader service or PDN branch that is being cleaned up.

LTE Deactivate EPS Bearer Context Request - Example Dump

Deactivate EPS Bearer Context Request
  Protocol discriminator: EPS session management
  EPS bearer identity: 6
  Procedure transaction identity: 4
  Message type: Deactivate EPS Bearer Context Request
  ESM cause: regular deactivation

How to read this dump

Start with the EPS bearer identity because it tells you exactly which active bearer the network wants to remove.
Then decide whether the request is releasing a dedicated bearer while the default bearer stays active, or whether it is part of wider PDN cleanup.
If the network keeps retransmitting the request, move quickly to T3495 supervision and check whether the accept branch is missing.

Important Information Elements

IE	Required	Description
`EPS bearer identity`	Yes	Identifies the bearer context the network wants the UE to deactivate.
`ESM cause`	Optional	May explain why the bearer is being deactivated and what broader branch is changing.
`Protocol configuration options`	Optional	May carry additional release-related configuration information.

Detailed field explanation

`EPS bearer identity`

Identifies the bearer context the network wants the UE to deactivate.

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.

`ESM cause`

May explain why the bearer is being deactivated and what broader branch is changing.

Presence: Optional

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.

`Protocol configuration options`

May carry additional release-related configuration information.

Presence: Optional

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.

What to check in logs and traces

Confirm which bearer identity the request targets.
Check whether it is releasing a dedicated bearer or a wider PDN branch.
Inspect ESM cause when present.
Correlate the request with the later Deactivate EPS Bearer Context Accept.
Check whether repeated request retransmissions point to missing UE completion.

Common Issues and Troubleshooting

A service-specific bearer disappears unexpectedly.

Likely cause: The network may have intentionally deactivated the dedicated bearer because the service branch ended or policy changed.

What to inspect: Check the targeted bearer identity, the earlier dedicated bearer activation branch, and the later accept response.

Next step: Treat it first as a deliberate bearer release before assuming a user-plane failure.

The network keeps sending bearer deactivation requests.

Likely cause: The branch may still be under T3495 supervision because the UE did not complete bearer deactivation cleanly.

What to inspect: Check whether Deactivate EPS Bearer Context Accept appears and whether the same bearer identity is repeated.

Next step: Read the trace as a bearer-release completion problem rather than only a session-management policy issue.

PDN cleanup looks incomplete or delayed.

Likely cause: The network may have requested bearer release, but one or more deactivation completion branches may still be missing.

What to inspect: Compare the deactivation request, bearer identity, and the matching accept timing across working and failing traces.

Next step: Follow the bearer deactivation branch end to end before concluding the PDN release logic is wrong.

LTE / 5G / Variant Comparison

Compared with Activate Dedicated EPS Bearer Context Request

Activate Dedicated EPS Bearer Context Request creates a service-specific bearer. Deactivate EPS Bearer Context Request removes a bearer that was already active.

Compared with Activate Default EPS Bearer Context Request

Activate Default EPS Bearer Context Request builds the first bearer for a PDN connection. Deactivate EPS Bearer Context Request tears down an existing bearer after the session branch changes or ends.

Compared with Service Request

Service Request restores use of existing EPS context. Deactivate EPS Bearer Context Request removes a bearer from an already active or recently active service branch.

FAQ

What is Deactivate EPS Bearer Context Request in LTE?

It is the EPS NAS session-management message the network sends to ask the UE to release an active bearer context.

What should I inspect first in this message?

Start with the EPS bearer identity, then decide whether the request is removing a dedicated bearer or a wider PDN branch.

Why is this message important in troubleshooting?

Because it explains why a bearer disappeared and whether the bearer-release branch completed cleanly.

What usually comes after this message?

The UE normally replies with Deactivate EPS Bearer Context Accept if it releases the requested bearer successfully.

Related message pages

Related Procedures

Related Tools

Use This Reference in Practice

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.