3GPP Scout / Reference / 5GS NAS timers / T3510

TS 24.501NAS timer

Timer T3510: 5GS mobility management, UE side

TS 24.501 V20.1.0Clause 10.2Table 10.2.1Checked 2026-10-15

In plain words

The UE starts T3510 when sending REGISTRATION REQUEST and starts T3511 or T3502 if it expires during initial registration or mobility and periodic registration update.

Our summary of the spec text quoted below.

What the spec says

Timer value

15s NOTE 7 NOTE 8 In WB-N1/CE mode, 85s For access via a satellite NG-RAN cell, 27s NOTE 12

Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.

Started when

Transmission of REGISTRATION REQUEST message

Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.

Stopped when

REGISTRATION ACCEPT message received or REGISTRATION REJECT message received

Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.

On expiry

Start T3511 or T3502 as specified in clause 5.5.1.2.7 if T3510 expired during registration procedure for initial registration. Start T3511 or T3502 as specified in clause 5.5.1.3.7 if T3510 expired during the registration procedure for mobility and periodic registration update

Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.

State

5GMM-REGISTERED-INITIATED

Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.

Same timer in EPS (TS 24.301)

TS 24.301 defines the corresponding timer for EPS. Its page quotes the EPS wording.

How this page was made

3GPP Scout built this page from TS 24.501 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 line was 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.