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Session Lifecycle⚓︎

Standard 3GPP session procedures on Expeto Edge (xCore): attach and registration, detach, idle-mode transitions, service request and paging, periodic updates, repeated sessions, the loss of a device without a detach, session release while registered and multiple simultaneous sessions. These tests confirm that a Mobile Asset provisioned in xControl behaves on the private network exactly as it would on a public mobile network.

ID Test Category Applies to
EXP-SES-001 UE-initiated attach Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-002 UE-initiated detach Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-003 Network-initiated detach Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-004 UE idle mode Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-005 UE-triggered service request Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-006 UE paging Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-007 Multiple UE attach Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-008 Repeated attach and detach cycles Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-009 Periodic tracking area or registration update Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-010 Implicit detach after loss of the device Functional 4G, 5G · Local radio · Single node, HA cluster, Geo-redundant
EXP-SES-011 Attach with an APN outside the System Profile Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-012 Session release and re-establishment while registered Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
EXP-SES-013 Multiple PDN connections Functional 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant

EXP-SES-001 — UE-initiated attach⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 15 min
Included in Installation and Upgrade Verification
Automated by Platform suite, 4G split core: session flow attach-detach (single run, mixed soak and weekly deep soak)
Platform suite, Kubernetes-operator managed core: session flow attach-detach, once per user plane
Release certification: subscriber lifecycle scenarios on the reference 5G configuration

Objective. A UE initiates an attach request to the network and is authenticated. After authentication the network obtains the UE's subscription data from the subscriber database and, based on the default APN and PDN/PDU context in that data, creates the default session. The UE is then attached to the network and passes data.

Preconditions

  • Mobile Asset
    • The UE's Mobile Asset is provisioned in xControl on the System under test, with state Active and status Provisioned or Disconnected.
  • Device
    • The UE is powered off or in airplane mode.
    • The UE has the APN of its System Profile configured.
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
  • Tooling and access
    • Log in to xControl with an account that can view the Mobile Asset under test.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.

Procedure

# Where Action Expected result
1 UE Power on the UE, or take it out of airplane mode, and wait for it to connect to the cellular network. The UE shows a cellular data connection.
2 UE Open a web page, or ping a known reachable host. The page loads, or the ping is answered.
3 xControl Open Mobile Assets and select the UE's IMSI. The Mobile Asset status is Connected and an IP address inside the System's range is shown.
4 xControl Scroll down to the Sessions section and select Session History. On 4G, an HSS entry Attached and a PGW entry Open with a start time and no end time are present; on 5G the same two entries appear, named after the subscriber database and the SMF.
5 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling, with no reject or failure message.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3), S6a / N8 (point 4).

4G (EPS) sequence

  1. Attach Request, carrying a PDN Connectivity Request (S1AP Initial UE Message)
  2. Identity Request / Identity Response, when the network does not hold the UE's identity
  3. Authentication Information Request / Answer on S6a, then Authentication Request / Authentication Response
  4. Security Mode Command / Security Mode Complete
  5. Update Location Request / Answer on S6a
  6. Create Session Request / Create Session Response on S11
  7. Initial Context Setup Request, carrying Attach Accept and Activate Default EPS Bearer Context Request
  8. Initial Context Setup Response
  9. Attach Complete, carrying Activate Default EPS Bearer Context Accept
  10. Modify Bearer Request / Modify Bearer Response on S11

5G (5GS) sequence

  1. Registration Request (NGAP Initial UE Message)
  2. Identity Request / Identity Response, when the network does not hold the UE's identity
  3. Authentication Request / Authentication Response, with the AUSF and UDM exchanges on the service-based interfaces
  4. Security Mode Command / Security Mode Complete
  5. Initial Context Setup Request, carrying Registration Accept
  6. Initial Context Setup Response, then Registration Complete
  7. PDU Session Establishment Request (UL NAS Transport)
  8. PFCP Session Establishment Request / Response on N4
  9. PDU Session Resource Setup Request, carrying PDU Session Establishment Accept
  10. PDU Session Resource Setup Response

Pass criteria

  • The UE obtains a data connection and passes traffic without manual intervention.
  • The IP address shown in xControl is inside the address range of the Mobile Asset's System.
  • The capture contains the complete sequence and no reject or failure message.

Evidence collected: 3GPP signalling capture (pcap); xControl session event log; UE connectivity check.
References: 3GPP TS 23.401 §5.3.2.1 (E-UTRAN Initial Attach); 3GPP TS 24.301 §5.5.1.2 (Attach procedure for EPS services); 3GPP TS 23.502 §4.2.2.2.2 (General Registration); 3GPP TS 23.502 §4.3.2.2.1 (UE Requested PDU Session Establishment).

EXP-SES-002 — UE-initiated detach⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 10 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
Included in Installation and Upgrade Verification
Automated by Platform suite, 4G split core: session flow attach-detach (single run, mixed soak and weekly deep soak)
Platform suite, Kubernetes-operator managed core: session flow attach-detach, once per user plane

Objective. The UE initiates a detach procedure and the network releases the session, the user-plane resources and the UE context, and xControl records the end of the session.

Preconditions

  • Tooling and access
    • Log in to xControl with an account that holds the ADMIN role.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 UE Power off the UE, or put it in airplane mode, and wait for it to disconnect from the network. The UE no longer shows a cellular connection.
3 xControl Open the Mobile Asset. The status changes to Disconnected within a reasonable time (nominally within 30 seconds).
4 xControl Scroll down to the Sessions section and select Session History. The PGW entry of the session is Closed with an end time.
5 CLI Run cd /lte, then read pgw -f imsi=<imsi> (4G), or cd /nr, then read smf -f imsi=<imsi> (5G). No session is listed for the IMSI.
6 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. Detach Request (UE originating; the switch-off indication is set when the UE powers off)
  2. Delete Session Request / Delete Session Response on S11
  3. Detach Accept (absent when the UE indicated switch-off)
  4. UE Context Release Command / UE Context Release Complete

5G (5GS) sequence

  1. Deregistration Request (UE originating)
  2. PFCP Session Deletion Request / Response on N4
  3. Deregistration Accept (absent when the UE indicated switch-off)
  4. UE Context Release Command / UE Context Release Complete

Pass criteria

  • xControl shows Disconnected within 30 seconds of the detach.
  • The session record is closed with an end time.
  • No session context remains for the IMSI on the session-management function.

Evidence collected: 3GPP signalling capture (pcap); xControl session event log; CLI output.
References: 3GPP TS 23.401 §5.3.8.2 (UE-initiated Detach procedure); 3GPP TS 23.502 §4.2.2.3.2 (UE-initiated Deregistration).

EXP-SES-003 — Network-initiated detach⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 10 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach

Objective. An administrator cancels a Mobile Asset's session from xControl. The subscriber database instructs the mobility function to detach the UE with re-attach required, the session and its resources are released, and the UE attaches again on its own with a new session.

Preconditions

  • Tooling and access
    • Log in to xControl with an account that holds the ADMIN role.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 xControl On the Mobile Asset's detail page, click the more button (...) and then Cancel Session. The action is accepted.
3 xControl Watch the Mobile Asset status. The status changes to Disconnected, then back to Connected within one minute as the UE re-attaches on its own.
4 xControl Scroll down to the Sessions section and select Session History. The PGW entry of the cancelled session is Closed; an HSS entry records the deregistration; a new PGW entry is Open.
5 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling; the Cancel Location Request carries the Reattach-Required flag and the Detach Request has detach type re-attach required.

Expected signalling

Capture points: S6a / N8 (point 4), S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. Cancel Location Request on S6a from the HSS to the MME, with the Reattach-Required flag set, and Cancel Location Answer
  2. Detach Request (network originating), detach type re-attach required
  3. Detach Accept
  4. Delete Session Request / Delete Session Response on S11
  5. UE Context Release Command / UE Context Release Complete
  6. Attach Request from the UE and the attach sequence of EXP-SES-001

5G (5GS) sequence

  1. Deregistration notification from the UDM to the AMF (Nudm_UECM_DeregistrationNotification), re-registration required
  2. Deregistration Request (UE terminated), re-registration required
  3. Deregistration Accept
  4. PFCP Session Deletion Request / Response on N4
  5. UE Context Release Command / UE Context Release Complete
  6. Registration Request from the UE and the registration sequence of EXP-SES-001

Pass criteria

  • The session is released without any action on the UE.
  • The Cancel Location Request carries the Reattach-Required flag and the UE re-attaches on its own within one minute.
  • A new session is open in xControl after the re-attach.

Postconditions

  • Leave the UE attached for the next procedure or detach it with EXP-SES-002.

Evidence collected: 3GPP signalling capture (pcap); xControl session event log.
References: 3GPP TS 23.401 §5.3.8.3 (MME-initiated Detach procedure); 3GPP TS 23.401 §5.3.8.4 (HSS-initiated Detach procedure); 3GPP TS 29.272 §5.2.2.2 (Cancel Location (CLR-Flags); 3GPP TS 23.502 §4.2.2.3.3 (Network-initiated Deregistration).

EXP-SES-004 — UE idle mode⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 20 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
Included in Installation and Upgrade Verification
Automated by Platform suite, 4G split core: session flow idle-reactivate
Platform suite, 4G split core: session flow idle-detach

Objective. A connected UE that stops generating traffic has its radio connection released after the radio's inactivity timer expires. The UE enters the idle state (ECM-IDLE in 4G, CM-IDLE in 5G) while it stays registered and keeps its session and IP address.

Preconditions

  • Device
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
    • A UE application that shows the radio connection state, or knowledge of the radio's inactivity timer.
  • Tooling and access
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Log in to xControl with an account that can view the Mobile Asset under test.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 UE Make sure the UE generates no data traffic and wait for the inactivity time defined by the radio configuration. The UE's radio connection is released while the UE remains registered.
3 CLI For a private radio, run cd /lte, then read mme -f imsi=<imsi> (4G), or cd /nr, then read amf <imsi> (5G). The context exists and its state (4G) or Status (5G) shows the UE as idle (ECM-IDLE or CM-IDLE).
4 xControl Open the Mobile Asset. The status is still Connected and the IP address is unchanged; the idle transition does not end the session.
5 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. UE Context Release Request from the eNodeB, cause user inactivity
  2. Release Access Bearers Request / Response on S11
  3. UE Context Release Command / UE Context Release Complete

5G (5GS) sequence

  1. UE Context Release Request from the gNodeB, cause user inactivity
  2. PFCP Session Modification Request / Response on N4, deactivating the N3 tunnel and enabling downlink buffering or notification
  3. UE Context Release Command / UE Context Release Complete

Pass criteria

  • The radio connection is released within the radio's configured inactivity time and the UE stays registered.
  • The session and IP address survive the idle transition.

Evidence collected: 3GPP signalling capture (pcap); CLI output.
References: 3GPP TS 23.401 §5.3.5 (S1 release procedure); 3GPP TS 23.502 §4.2.6 (AN release).

EXP-SES-005 — UE-triggered service request⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 15 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
EXP-SES-004 — UE idle mode
Included in Installation and Upgrade Verification
Automated by Platform suite, 4G split core: session flow idle-reactivate

Objective. A registered UE in idle state generates new uplink traffic. The network re-establishes the radio connection and the user-plane path with a service request, without a new attach, and the UE keeps its IP address.

Preconditions

  • Device
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
  • Tooling and access
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Log in to xControl with an account that holds the ADMIN role.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 — Execute EXP-SES-004 — UE idle mode as a prerequisite procedure. As defined in EXP-SES-004.
3 UE Open a web page, or ping a known reachable host. The UE regains its radio connection and the page loads, or the ping is answered.
4 xControl Open the Mobile Asset. The status is Connected with the same IP address as before the idle period, and no new session was created in the Event Log.
5 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling; there is no Attach Request or Registration Request.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. Service Request (S1AP Initial UE Message)
  2. Initial Context Setup Request / Initial Context Setup Response
  3. Modify Bearer Request / Modify Bearer Response on S11

5G (5GS) sequence

  1. Service Request (NGAP Initial UE Message)
  2. Initial Context Setup Request, carrying Service Accept, and Initial Context Setup Response
  3. PFCP Session Modification Request / Response on N4, re-activating the N3 tunnel

Pass criteria

  • Traffic resumes without a new attach or registration and with the same IP address.

Evidence collected: 3GPP signalling capture (pcap); xControl session event log.
References: 3GPP TS 23.401 §5.3.4.1 (UE triggered Service Request); 3GPP TS 23.502 §4.2.3.2 (UE Triggered Service Request).

EXP-SES-006 — UE paging⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 20 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
EXP-SES-004 — UE idle mode

Objective. Downlink traffic arrives for a UE in idle state. The user plane reports the data, the network pages the UE, the UE responds with a service request and the traffic is delivered.

Preconditions

  • Tooling and access
    • A host on the enterprise LAN (SGi / N6 side) that can send ping or other traffic to the UE's IP address.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Log in to xControl with an account that holds the ADMIN role.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 — Execute EXP-SES-004 — UE idle mode as a prerequisite procedure. As defined in EXP-SES-004.
3 Test host Send a ping (or other traffic the UE answers) from the LAN host toward the IP address of the UE. After a short delay the ping is answered. If the UE does not respond to ICMP, use a protocol it answers.
4 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling.

Expected signalling

Capture points: S11 / N4 (point 3), S1-MME / N2 (point 1).

4G (EPS) sequence

  1. Downlink Data Notification / Downlink Data Notification Acknowledge on S11
  2. Paging (S1AP) on every eNodeB of the tracking area list
  3. Service Request from the UE
  4. Initial Context Setup Request / Response
  5. Modify Bearer Request / Modify Bearer Response on S11, then the buffered downlink data is delivered

5G (5GS) sequence

  1. PFCP Session Report Request / Response on N4, reporting downlink data
  2. Paging (NGAP) on every gNodeB of the registration area
  3. Service Request from the UE
  4. Initial Context Setup Request, carrying Service Accept, and Initial Context Setup Response
  5. PFCP Session Modification Request / Response on N4, then the buffered downlink data is delivered

Pass criteria

  • The UE is paged and answers; the first or one of the first downlink packets is delivered after the service request.

Evidence collected: 3GPP signalling capture (pcap).
References: 3GPP TS 23.401 §5.3.4.3 (Network Triggered Service Request); 3GPP TS 23.502 §4.2.3.3 (Network Triggered Service Request).

EXP-SES-007 — Multiple UE attach⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 30 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
Included in Installation and Upgrade Verification
Automated by Platform suite, 4G split core: mixed-flow soak (100 live sessions, random flow per session) and weekly deep soak

Objective. Several UEs connect to the network at the same time, each obtains its own address and service, and xControl shows all of them connected.

Preconditions

  • Mobile Asset
    • Several Mobile Assets are provisioned in xControl on the System under test, one per UE, each with state Active.
  • Device
    • The UE is powered off or in airplane mode.
    • The UE has the APN of its System Profile configured.
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
  • Tooling and access
    • Log in to xControl with an account that can view the Mobile Asset under test.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 UE Repeat the previous procedure for each remaining provisioned UE, without detaching the ones already attached. Every UE shows the results of EXP-SES-001.
3 xControl Open Mobile Assets filtered by the System. All the UEs are Connected at the same time, each with a distinct IP address.

Pass criteria

  • Every UE is connected and passing traffic simultaneously, with no two UEs sharing an address.

Evidence collected: xControl Mobile Asset status; UE connectivity check.

EXP-SES-008 — Repeated attach and detach cycles⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 30 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
EXP-SES-002 — UE-initiated detach
Automated by Platform suite, Kubernetes-operator managed core: session flow reattach
Platform suite, 4G split core: session flow attach-detach (single run, mixed soak and weekly deep soak)

Objective. A UE attaches and detaches repeatedly. Every cycle produces a complete session, every session is recorded and closed, and no context is left behind in the core after the last detach.

Preconditions

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 — Execute EXP-SES-002 — UE-initiated detach as a prerequisite procedure. As defined in EXP-SES-002.
3 UE Repeat the attach and detach four more times, waiting for Connected and Disconnected in xControl on each cycle. Every cycle reaches Connected and then Disconnected.
4 xControl Scroll down to the Sessions section and select Session History. Five PGW entries exist, each Closed with a start and an end time, and no entry remains Open.
5 CLI Run read mme -f imsi=<imsi> (or read amf <imsi>) and read pgw -f imsi=<imsi> (or read smf -f imsi=<imsi>). No context and no session is listed for the IMSI.
6 xControl Compare the IP addresses of the five sessions. Each address is inside the System's range. A dynamically addressed Mobile Asset may receive the same or a different address on each cycle; a statically addressed one receives its pinned address every time.
7 Capture Inspect the five Attach Requests (or Registration Requests) in the capture. The first carries the IMSI (or SUCI); every later one carries the GUTI (or 5G-GUTI) assigned by the previous cycle, and the IMSI does not appear in clear again.

Pass criteria

  • Five of five cycles complete.
  • Five closed session records and no open record exist for the IMSI.
  • No residual context remains in the core after the last detach.
  • The permanent identity is sent in clear at most once; every later attach uses the temporary identity.

Evidence collected: xControl session event log; CLI output; 3GPP signalling capture (pcap).
References: 3GPP TS 23.401 §5.3.10.3 (User Identity Confidentiality (GUTI reallocation)); 3GPP TS 24.501 §5.4.4 (Generic UE configuration update (5G-GUTI reallocation)).

EXP-SES-009 — Periodic tracking area or registration update⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 1 h 30 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
EXP-SES-004 — UE idle mode

Objective. A UE that stays idle beyond the periodic update timer performs a periodic tracking area update (4G) or periodic registration update (5G), the network accepts it, and the UE stays registered with its session intact.

Preconditions

  • Platform
    • You know the periodic update timer (T3412 in 4G, T3512 in 5G) that the xCore assigns to the UE. Read it with cd /lte/debug/ashmme, then show timer (4G), or from the Attach Accept or Registration Accept in the capture of EXP-SES-001. To shorten the wait, set it for the test with update timer t3412=<seconds> and restore it afterwards.
  • Tooling and access
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Log in to xControl with an account that can view the Mobile Asset under test.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 — Execute EXP-SES-004 — UE idle mode as a prerequisite procedure. As defined in EXP-SES-004.
3 UE Leave the UE idle, with no traffic, for longer than the periodic update timer. The UE stays registered.
4 Capture Inspect the signalling capture after the timer has expired. The messages match the sequence under Expected signalling; the update type is periodic.
5 xControl Open the Mobile Asset. The status is unchanged (Connected) and no new session was created.
6 UE Open a web page, or ping a known reachable host. Traffic resumes with a service request, as in EXP-SES-005.

Expected signalling

Capture points: S1-MME / N2 (point 1).

4G (EPS) sequence

  1. Tracking Area Update Request, update type periodic updating
  2. Tracking Area Update Accept (with a new GUTI when the network reallocates it)
  3. Tracking Area Update Complete, when a new GUTI was allocated
  4. UE Context Release Command / UE Context Release Complete

5G (5GS) sequence

  1. Registration Request, registration type periodic registration updating
  2. Registration Accept (with a new 5G-GUTI when the network reallocates it)
  3. Registration Complete, when a new 5G-GUTI was allocated
  4. UE Context Release Command / UE Context Release Complete

Pass criteria

  • The periodic update is accepted and the UE stays registered with its session and address.
  • The update occurs no later than the periodic timer value signalled in the Attach Accept or Registration Accept plus 60 seconds.

Postconditions

  • Restore the periodic timer if it was shortened for the test.

Evidence collected: 3GPP signalling capture (pcap); xControl session event log.
References: 3GPP TS 23.401 §5.3.3.0 (Triggers for tracking area update); 3GPP TS 24.301 §5.5.3.2 (Normal and periodic tracking area updating procedure); 3GPP TS 24.501 §5.5.1.3 (Registration procedure for mobility and periodic registration update).

EXP-SES-010 — Implicit detach after loss of the device⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio · Single node, HA cluster, Geo-redundant
Duration About 2 h
Prerequisite procedures EXP-SES-001 — UE-initiated attach

Objective. A UE disappears from coverage without detaching. The network keeps its context until the reachability and implicit detach timers expire, then detaches it implicitly, closes the session with a cause, and leaves no context behind.

Preconditions

  • Platform
    • You know the periodic update, mobile reachable and implicit detach timers the xCore applies (cd /lte/debug/ashmme, then show timer); the time to implicit detach is their sum. To shorten the wait, set them for the test with update timer t3412=<s> mobileReachableTimer=<s> valimplicitDetachTimerval=<s> and restore them afterwards.
  • Device
    • A way to remove the UE from coverage abruptly (an RF-shielded box, or moving the UE out of coverage) without it sending a detach.
  • Tooling and access
    • Log in to xControl with an account that holds the ADMIN role.
    • Access to the CLI.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 UE Place the UE in the shielded box, or move it out of coverage, without powering it off or enabling airplane mode. Note the time. The UE loses coverage; no Detach Request or Deregistration Request appears in the capture.
3 xControl Open the Mobile Asset immediately after. The status is still Connected; the network has not yet detected the loss.
4 CLI Run read mme -f imsi=<imsi> (or read amf <imsi>) at intervals until the implicit detach timer has expired. The context exists until the timers expire, then disappears.
5 xControl Open the Event Log section and select Session after the timers have expired. The PGW entry is Closed with an end time, and the record carries a cause code for the implicit detach.
6 UE Take the UE out of the box, or back into coverage. The UE attaches again as in EXP-SES-001 and a new session opens.

Pass criteria

  • The session is closed with a cause no later than the sum of the configured periodic, mobile reachable and implicit detach timers plus 60 seconds.
  • No context remains for the IMSI once the session is closed.
  • The UE regains service without manual intervention when coverage returns.

Postconditions

  • Restore the timers if they were shortened for the test.

Evidence collected: xControl session event log; CLI output.
References: 3GPP TS 23.401 §5.3.8.3 (MME-initiated Detach procedure (implicit detach)); 3GPP TS 24.301 §5.3.7 (Handling of the periodic tracking area update timer and mobile reachable timer); 3GPP TS 24.501 §5.3.7 (Handling of the periodic registration update timer and mobile reachable timer).

EXP-SES-011 — Attach with an APN outside the System Profile⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 20 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach

Objective. A UE requests a PDN connection or PDU session for an APN (DNN) that is not in its Mobile Asset's System Profile. The network rejects the request with a cause the UE understands, and correcting the APN on the UE restores service.

Preconditions

  • Mobile Asset
    • The UE's Mobile Asset is provisioned in xControl on the System under test, with state Active and status Provisioned or Disconnected.
  • Device
    • The UE's data APN is set to a name that is not in the Mobile Asset's System Profile (for example wrong.example.com).
    • The UE is powered off or in airplane mode.
  • Tooling and access
    • Log in to xControl with an account that can view the Mobile Asset under test.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
  • Procedures executed first

Procedure

# Where Action Expected result
1 UE Power on the UE, or take it out of airplane mode, and wait for it to attempt to connect. The UE registers but obtains no data connection, or fails to attach, depending on the radio access technology and device.
2 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling; the reject cause identifies the APN or DNN as unknown.
3 xControl Open the Mobile Asset. The status is not Connected; no PGW entry is Open.
4 UE Correct the APN to the one in the System Profile and toggle airplane mode. The UE connects as in EXP-SES-001.

Expected signalling

Capture points: S1-MME / N2 (point 1).

4G (EPS) sequence

  1. Attach Request, carrying a PDN Connectivity Request with the unknown APN
  2. Authentication and Security Mode exchanges complete
  3. Attach Reject, or Attach Accept followed by PDN Connectivity Reject, with an ESM cause that names the APN as missing or unknown

5G (5GS) sequence

  1. Registration Request, Authentication, Security Mode; Registration Accept
  2. PDU Session Establishment Request with the unknown DNN
  3. PDU Session Establishment Reject with a 5GSM cause that names the DNN as missing or unknown

Pass criteria

  • No data session is established for the unknown APN.
  • The reject carries ESM cause #27 (4G) or 5GSM cause #27 (5G), missing or unknown APN or DNN.
  • Service is restored by correcting the APN on the UE, with no change on the platform.

Evidence collected: 3GPP signalling capture (pcap); xControl Mobile Asset status.
References: 3GPP TS 24.301 §6.5.1.4 (UE requested PDN connectivity procedure not accepted by the network); 3GPP TS 24.501 §6.4.1.4 (UE-requested PDU session establishment procedure not accepted by the network).

EXP-SES-012 — Session release and re-establishment while registered⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 20 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach
EXP-SES-013 — Multiple PDN connections

Objective. A registered UE releases one data session without deregistering, the network tears down that session's user-plane resources and closes its record, and the UE establishes a new session afterwards, still without a new attach or registration.

Preconditions

  • Device
    • 5G, a UE whose mobile-data switch releases the PDU session. 4G, the UE has two PDN connections (EXP-SES-013), so that releasing one leaves the UE attached.
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
  • Tooling and access
    • Log in to xControl with an account that holds the ADMIN role.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Access to the CLI.
  • Procedures executed first

Procedure

# Where Action Expected result
1 — Execute EXP-SES-001 — UE-initiated attach as a prerequisite procedure. As defined in EXP-SES-001.
2 UE Release the session. 5G, switch mobile data off. 4G, disable the second APN so the UE disconnects that PDN. The UE stays registered on the network.
3 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling; there is no Detach Request or Deregistration Request.
4 CLI Run read amf <imsi> (5G) or read mme -f imsi=<imsi> (4G), then read smf -f imsi=<imsi> or read pgw -f imsi=<imsi>. The mobility context still exists; the released session is no longer listed.
5 xControl Open the Mobile Asset and its Event Log. The released session's PGW entry is Closed; 5G, the status is Disconnected while no session exists.
6 UE Re-establish the session. 5G, switch mobile data on. 4G, enable the second APN again. The UE obtains a data connection and passes traffic.
7 Capture Inspect the signalling capture. A new PDU Session Establishment (or PDN Connectivity Request) completes; there is no Registration Request or Attach Request.
8 xControl Open the Mobile Asset. The status is Connected with a new Open session record.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. PDN Disconnect Request from the UE for the second PDN
  2. Delete Session Request / Delete Session Response on S11
  3. Deactivate EPS Bearer Context Request / Accept, and E-RAB Release Command / Response
  4. Later, PDN Connectivity Request, Create Session Request / Response, Activate Default EPS Bearer Context Request / Accept, E-RAB Setup Request / Response

5G (5GS) sequence

  1. PDU Session Release Request from the UE (UL NAS Transport)
  2. PFCP Session Deletion Request / Response on N4
  3. PDU Session Resource Release Command / Response, carrying PDU Session Release Command
  4. PDU Session Release Complete
  5. Later, PDU Session Establishment Request, PFCP Session Establishment, PDU Session Resource Setup Request / Response carrying PDU Session Establishment Accept

Pass criteria

  • The session is released and re-established with no detach, deregistration, attach or registration.
  • The released session's record is closed and the new session's record is open, each with its own start time.
  • No user-plane resource remains for the released session.

Evidence collected: 3GPP signalling capture (pcap); CLI output; xControl session event log.
References: 3GPP TS 23.502 §4.3.4.2 (UE or network requested PDU Session Release); 3GPP TS 24.501 §6.4.3 (UE-requested PDU session release procedure); 3GPP TS 23.401 §5.10.3 (UE requested PDN disconnection); 3GPP TS 24.301 §6.5.2 (UE requested PDN disconnect procedure).

EXP-SES-013 — Multiple PDN connections⚓︎

Attribute Value
Status Accepted
Category Functional
Components xCore, xControl
Applies to 4G, 5G · Local radio, Public radio · Single node, HA cluster, Geo-redundant
Duration About 30 min
Prerequisite procedures EXP-SES-001 — UE-initiated attach

Objective. A UE whose System Profile holds two APN Profiles establishes two PDN connections (4G) or two PDU sessions (5G) at the same time, each with its own address and record, passes traffic on both, and can release one without affecting the other.

Preconditions

  • Platform
    • The Mobile Asset's System Profile contains two APN Profiles, A and B, each with its own address range and egress on the enterprise network.
  • Device
    • The UE has both APNs configured and set to connect (for example APN A as the default data APN and APN B as a second data APN).
    • The UE has a web browser or a terminal application that can send ICMP echo requests (ping).
  • Tooling and access
    • Log in to xControl with an account that holds the ADMIN role.
    • Start a 3GPP signalling capture (pcap) with your preferred tool on the interfaces the procedure exercises.
    • Access to the CLI.
    • A host reachable through each APN's egress.
  • Procedures executed first

Procedure

# Where Action Expected result
1 UE Power on the UE, or take it out of airplane mode, and wait for both APNs to connect. The UE shows two active data connections.
2 Capture Inspect the signalling capture. The messages match the sequence under Expected signalling; two default bearers (4G) or two PDU sessions (5G) are set up with distinct identifiers.
3 CLI Run read pgw -f imsi=<imsi> (4G) or read smf -f imsi=<imsi> (5G). Two sessions are listed for the IMSI, with different bearer or PDU session identifiers and different addresses.
4 xControl Open the Mobile Asset and its Event Log. Two PGW entries are Open, one per APN name, each with its address.
5 UE Ping the host behind APN A and the host behind APN B. Both pings are answered.
6 UE Disable APN B on the UE. The APN B session is released (EXP-SES-012) and the APN A connection is unaffected.
7 UE Ping the host behind APN A again. The ping is answered without interruption.

Expected signalling

Capture points: S1-MME / N2 (point 1), S11 / N4 (point 3).

4G (EPS) sequence

  1. Attach with the first PDN as in EXP-SES-001
  2. PDN Connectivity Request for the second APN
  3. Create Session Request / Create Session Response on S11 for the second PDN
  4. E-RAB Setup Request carrying Activate Default EPS Bearer Context Request, E-RAB Setup Response, Activate Default EPS Bearer Context Accept

5G (5GS) sequence

  1. Registration as in EXP-SES-001
  2. Two PDU Session Establishment Requests with different PDU session identifiers and DNNs
  3. Two PFCP Session Establishment Request / Response exchanges on N4
  4. Two PDU Session Resource Setup Request / Response exchanges carrying PDU Session Establishment Accept

Pass criteria

  • Two sessions with distinct identifiers and addresses exist for the UE at the same time and both pass traffic.
  • Each session has its own open record in xControl, attributed to its APN.
  • Releasing one session leaves the other passing traffic without interruption.

Evidence collected: 3GPP signalling capture (pcap); CLI output; xControl session event log; ICMP result from the UE.
References: 3GPP TS 23.401 §5.10.2 (UE requested PDN connectivity); 3GPP TS 24.301 §6.5.1 (UE requested PDN connectivity procedure); 3GPP TS 23.502 §4.3.2.2.1 (UE Requested PDU Session Establishment).