Timer value
8s In WB-S1/CE mode, 16s NOTE 4
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
3GPP Scout / Reference / EPS NAS timers / Timers T3485, T3486 and T3495
TS 24.301NAS timer
Timers T3485, T3486 and T3495: EPS bearer context command retransmission by the MME
Covers
TS 24.301 words these values in parallel, so they share this page. Each has its own section with the spec text and a plain explanation.
Timer T3485: EPS session management, network side
In plain words
The network starts T3485 when it sends an ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST or ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST and retransmits the same message when the timer expires.
Our summary of the spec text quoted below.
Started when
ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST sent ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST sent
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
On expiry
Retransmission of the same message
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Stopped when
ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT received or ACTIVATE DEFAULT EPS BEARER CONTEXT REJECT received or ACTIVATE DEDICATED EPS BEARER CONTEXT ACCEPT received or ACTIVATE DEDICATED EPS BEARER CONTEXT REJECT received
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
State
BEARER CONTEXT ACTIVE PENDING
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Timer T3486: EPS session management, network side
In plain words
The network starts T3486 when it sends a MODIFY EPS BEARER CONTEXT REQUEST and retransmits the request when the timer expires.
Our summary of the spec text quoted below.
Timer value
8s In WB-S1/CE mode, 16s NOTE 4
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Started when
MODIFY EPS BEARER CONTEXT REQUEST sent
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
On expiry
Retransmission of MODIFY EPS BEARER CONTEXT REQUEST
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Stopped when
MODIFY EPS BEARER CONTEXT ACCEPT received or MODIFY EPS BEARER CONTEXT REJECT received
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
State
BEARER CONTEXT MODIFY PENDING
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Timer T3495: EPS session management, network side
In plain words
The network starts T3495 when it sends a DEACTIVATE EPS BEARER CONTEXT REQUEST and retransmits the request when the timer expires.
Our summary of the spec text quoted below.
Timer value
8s In WB-S1/CE mode, 16s NOTE 4
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Started when
DEACTIVATE EPS BEARER CONTEXT REQUEST sent
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
On expiry
Retransmission of DEACTIVATE EPS BEARER CONTEXT REQUEST
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Stopped when
DEACTIVATE EPS BEARER CONTEXT ACCEPT received
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
State
BEARER CONTEXT INACTIVE PENDING
Source: 3GPP TS 24.301 V20.1.0, clause 10.3, table 10.3.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
How this page was made
3GPP Scout built this page from TS 24.301 V20.1.0 as indexed on 2026-10-15. The quotes are copied from the spec, and code checks each one against the stored text and the 3GPP archive file before publishing. The plain-words lines were written by an AI model (GPT-6 Sol) and checked against the quotes by a second AI model from another company (Claude Opus 5.5). The official 3GPP text governs.