Tech-invite3GPPspaceIETF RFCsSIP
Quick21222324252627282931323334353637384‑5x

Content for  TS 23.122  Word version:  18.1.0

Top   Top   Up   Prev   Next
1…   1.2   2   3…   4…   4.4…   4.5…   4.9…   5…   A…   C…   C.2   C.3   C.4…   C.5   C.6   C.7   C.8…

 

4.9  SNPN selection process |R16|p. 58

4.9.1  Generalp. 58

The MS operating in SNPN access mode shall perform the SNPN selection process.
The MS not operating in SNPN access mode shall not perform the SNPN selection process.
There are two SNPN selection modes - automatic SNPN selection mode and manual SNPN selection mode.
In the SNPN selection process, the MS shall consider only the access networks of the NG-RAN access technology.

4.9.2  Registration on an SNPNp. 58

The MS shall perform registration on the SNPN if the MS is capable of services which require registration. In both automatic SNPN selection mode and manual SNPN selection mode, the concept of registration on an SNPN is used. An MS successfully registers on an SNPN if:
  1. the MS has found a suitable cell of the SNPN to camp on; and
  2. an LR request from the MS has been accepted in the registration area of the cell on which the MS is camped.

4.9.3  SNPN selectionp. 58

4.9.3.0  Generalp. 58

The ME is configured with a "list of subscriber data" containing zero or more entries. Each entry of the "list of subscriber data" consists of:
a)
a subscriber identifier in the form of a SUPI with the SUPI format "network specific identifier" containing a network-specific identifier or with the SUPI format "IMSI" containing an IMSI, except when the subscribed SNPN uses:
  1. the EAP based primary authentication and key agreement procedure using the EAP-AKA'; or
  2. the 5G AKA based primary authentication and key agreement procedure;
  • with the SUPI format "network specific identifier"; or
  • with the SUPI format "IMSI", if the subscribed SNPN has an assigned PLMN ID.
b)
credentials except when the subscribed SNPN uses:
  1. the EAP based primary authentication and key agreement procedure using the EAP-AKA'; or
  2. the 5G AKA based primary authentication and key agreement procedure.
If the MS supports access to an SNPN using credentials from a credentials holder, the credentials can include an indication to use MSK for derivation of KAUSF after success of primary authentication and key agreement procedure;
ba)
optionally, a routing indicator, except when the subscribed SNPN uses:
  1. the EAP based primary authentication and key agreement procedure using the EAP-AKA'; or
  2. the 5G AKA based primary authentication and key agreement procedure;
bb)
optionally, the protection scheme identifier as specified in TS 33.501, except when the subscribed SNPN uses:
  1. the EAP based primary authentication and key agreement procedure using the EAP-AKA'; or
  2. the 5G AKA based primary authentication and key agreement procedure;
If the protection scheme identifier is configured in the entry of the "list of subscriber data" and not set to "null-scheme", the entry of the "list of subscriber data" also contains the home network public key and the home network public key identifier as specified in in TS 33.501;
c)
an SNPN identity of the subscribed SNPN;
d)
optionally, the unified access control configuration indicating for which access identities (see TS 24.501) the ME is configured, when the MS accesses an SNPN using the entry.
Access identity 11 or 15, if configured, is applicable for the MS only in the subscribed SNPN.
Access identity 12, 13 or 14, if configured, is applicable for the MS only:
  1. in the subscribed SNPN; and
  2. if the MCC of the SNPN identity of the subscribed SNPN is not the MCC of value 999, in the non-subscribed SNPNs of the same country as the subscribed SNPN;
Access identity 1 or 2, if configured, is applicable for the MS only:
  1. in the subscribed SNPN;
  2. if the MCC of the SNPN identity of the subscribed SNPN is not the MCC of value 999, in the non-subscribed SNPNs of the same country as the subscribed SNPN; and
  3. in an SNPN equivalent to the subscribed SNPN;
e)
zero or more sets of pre-configured URSP rules (see TS 24.526), each set for the subscribed SNPN or a non-subscribed SNPN;
f)
optionally, the default configured NSSAI (see TS 24.501);
g)
optionally, if the MS supports access to an SNPN using credentials from a credentials holder, the SNPN selection parameters, consisting of:
  1. a user controlled prioritized list of preferred SNPNs, where each entry contains an SNPN identity;
  2. a credentials holder controlled prioritized list of preferred SNPNs, where each entry contains an SNPN identity; and
  3. a credentials holder controlled prioritized list of Group IDs for Network Selection (GINs); and
h)
optionally:
  1. an indication of whether the MS shall ignore all warning messages received in the subscribed SNPN; and
  2. an indication of whether the MS shall ignore all warning messages received in an SNPN other than the subscribed SNPN.
The MS which supports onboarding services in SNPN shall be pre-configured with default UE credentials for primary authentication and may be pre-configured with onboarding SNPN selection information. Contents of the onboarding SNPN selection information are MS implementation specific. Contents of default UE credentials for primary authentication are out of scope of 3GPP.
Additionally, if the MS has a USIM with a PLMN subscription, the ME may be configured with the SNPN selection parameters associated with the PLMN subscription, consisting of:
  1. a user controlled prioritized list of preferred SNPNs, where each entry contains an SNPN identity;
  2. a credentials holder controlled prioritized list of preferred SNPNs, where each entry contains an SNPN identity; and
  3. a credentials holder controlled prioritized list of GINs;
and with the following configuration parameters associated with the PLMN subscription:
  1. zero or more sets of pre-configured URSP rules (see TS 24.526), each set for the HPLMN or a non-subscribed SNPN.
The MS shall maintain a list of "temporarily forbidden SNPNs" and a list of "permanently forbidden SNPNs" in the ME. Each entry of those lists consists of an SNPN identity. If the MS supports access to an SNPN using credentials from a credentials holder, the MS shall maintain one list of "temporarily forbidden SNPNs" and one list of "permanently forbidden SNPNs" per entry of the "list of subscriber data" or the PLMN subscription, and shall use the lists associated with the selected entry of the "list of subscriber data" or the selected PLMN subscription. In addition, if the MS supports onboarding services in SNPN, a "permanently forbidden SNPNs" list for onboarding services and a "temporarily forbidden SNPNs" list for onboarding services shall be maintained.
The MS shall add an SNPN to the list of "temporarily forbidden SNPNs" (for onboarding services, if the MS is registered for onboarding services in SNPN or performing initial registration for onboarding services in SNPN) which is, if the MS supports access to an SNPN using credentials from a credentials holder, associated with the selected entry of the "list of subscriber data" or the selected PLMN subscription, if a message with cause value #74 "Temporarily not authorized for this SNPN" (see TS 24.501) is received by the MS in response to an LR request from the SNPN. In addition, if:
  • the message is integrity-protected; or
  • the message is not integrity-protected, and the value of the SNPN-specific attempt counter for that SNPN is equal to the MS implementation specific maximum value as defined in TS 24.501;
then the MS shall start an MS implementation specific timer not shorter than 60 minutes.
The MS shall remove an SNPN from the list of "temporarily forbidden SNPNs" (for onboarding services, if the MS is registered for onboarding services in SNPN or performing initial registration for onboarding services in SNPN) which is, if the MS supports access to an SNPN using credentials from a credentials holder, associated with the selected entry of the "list of subscriber data" or the selected PLMN subscription, if:
  1. there is a successful LR after a subsequent manual selection of the SNPN;
  2. the MS implementation specific timer not shorter than 60 minutes expires;
  3. the MS is configured to use timer T3245 and timer T3245 expires;
  4. the MS is not configured to use timer T3245, the timer T3247 expires and the value of the SNPN-specific attempt counter for that SNPN is less than the MS implementation specific maximum value as defined in TS 24.501;
  5. the MS is switched off;
  6. an entry of the "list of subscriber data" with the subscribed SNPN identity identifying the SNPN is updated or the USIM is removed if:
    • EAP based primary authentication and key agreement procedure using EAP-AKA'; or
    • 5G AKA based primary authentication and key agreement procedure;
    was performed in the selected SNPN; or
  7. the selected entry of the "list of subscriber data" is updated or USIM is removed for the selected PLMN subscription.
If an SNPN is removed from the list of "temporarily forbidden SNPNs" list, the MS shall stop the MS implementation specific timer not shorter than 60 minutes, if running.
The MS shall add an SNPN to the list of "permanently forbidden SNPNs" (for onboarding services, if the MS is registered for onboarding services in SNPN or performing initial registration for onboarding services in SNPN) which is, if the MS supports access to an SNPN using credentials from a credentials holder, associated with the selected entry of the "list of subscriber data" or the selected PLMN subscription, if a message with cause value #75 "Permanently not authorized for this SNPN", #3 "Illegal UE" (applicable in an onboarding SNPN only), #6 "Illegal ME" (applicable in an onboarding SNPN only), or #7 "5GS services not allowed" (applicable in an onboarding SNPN only) (see TS 24.501) is received by the MS in response to an LR request from the SNPN.
The MS shall remove an SNPN from the list of "permanently forbidden SNPNs" (for onboarding services, if the MS is registered for onboarding services in SNPN or performing initial registration for onboarding services in SNPN) which is, if the MS supports access to an SNPN using credentials from a credentials holder, associated with the selected entry of the "list of subscriber data" or the selected PLMN subscription, if:
  1. there is a successful LR after a subsequent manual selection of the SNPN;
  2. the MS is configured to use timer T3245 and timer T3245 expires;
  3. the MS is not configured to use timer T3245, the timer T3247 expires and the value of the SNPN-specific attempt counter for that SNPN is less than the MS implementation specific maximum value as defined in TS 24.501;
  4. an entry of the "list of subscriber data" with the subscribed SNPN identity identifying the SNPN is updated or the USIM is removed if:
    • EAP based primary authentication and key agreement procedure using EAP-AKA'; or
    • 5G AKA based primary authentication and key agreement procedure;
    was performed in the selected SNPN; or
  5. the selected entry of the "list of subscriber data" is updated or USIM is removed for the selected PLMN subscription.
When the MS reselects to a cell in a shared network, and the cell is a suitable cell for multiple SNPN identities received in the broadcast information as specified in TS 38.331, the AS indicates these multiple SNPN identities to the NAS according to TS 38.304. The MS shall select one of these SNPNs. If the registered SNPN is available among these SNPNs, the MS shall not select a different SNPN.
The MS operating in SNPN access mode shall maintain one or more lists of "5GS forbidden tracking areas for roaming", each associated with an SNPN and, if the MS supports access to an SNPN using credentials from a credentials holder, entry of the "list of subscriber data" or the PLMN subscription. The MS shall use the list of "5GS forbidden tracking areas for roaming" associated with the selected SNPN and, if the MS supports access to an SNPN using credentials from a credentials holder, the selected entry of the "list of subscriber data" or the selected PLMN subscription. If the MS selects a new SNPN, the MS shall keep the list of "5GS forbidden tracking areas for roaming" associated with the previously selected SNPN and, if the MS supports access to an SNPN using credentials from a credentials holder, the selected entry of the "list of subscriber data" or the selected PLMN subscription. If the number of the lists to be kept is higher than supported, the MS shall delete the oldest stored list of "5GS forbidden tracking areas for roaming". The MS shall delete all lists of "5GS forbidden tracking areas for roaming", when the MS is switched off and periodically (with period in the range 12 to 24 hours). The MS shall delete the list of "5GS forbidden tracking areas for roaming" associated with an SNPN:
  1. when the entry with the subscribed SNPN identifying the SNPN in the "list of subscriber data" is updated;
  2. when the USIM is removed if:
    • the EAP based primary authentication and key agreement procedure using the EAP-AKA'; or
    • the 5G AKA based primary authentication and key agreement procedure;
    was performed in the selected SNPN; or
  3. if the MS supports access to an SNPN using credentials from a credentials holder, when the list of "5GS forbidden tracking areas for roaming" is associated with:
    • the entry of the "list of subscriber data" and the entry of the "list of subscriber data" is updated; or
    • the PLMN subscription and USIM is removed.
If a message with cause value #15 (see TS 24.501) is received by an MS operating in SNPN access mode, the TA is added to the list of "5GS forbidden tracking areas for roaming" of the selected SNPN and, if the UE supports access to an SNPN using credentials from a credentials holder, the selected entry of the "list of subscriber data" or the selected PLMN subscription,. The MS shall then search for a suitable cell in the same SNPN but belonging to a TA which is not in the "5GS forbidden tracking areas for roaming" list of the selected SNPN and, if the UE supports access to an SNPN using credentials from a credentials holder, the selected entry of the "list of subscriber data" or the selected PLMN subscription.
The MS should maintain a list of SNPNs for which the N1 mode capability was disabled due to receipt of a reject from the network with 5GMM cause #27 "N1 mode not allowed". When the MS disables its N1 mode capability due to receipt of a reject from an SNPN with 5GMM cause #27 "N1 mode not allowed":
  • the MS should add the SNPN identity of the SNPN which sent a reject with 5GMM cause #27 "N1 mode not allowed" to the list of SNPNs for which the N1 mode capability was disabled and should start timer TJ if timer TJ is not already running. The number of SNPNs for which the N1 mode capability was disabled that the MS can store is implementation specific, but it shall be at least one. The value of timer TJ is MS implementation specific;
  • in automatic SNPN selection, the MS shall not select an SNPN for which the N1 mode capability was disabled as SNPN selection candidates, unless no other SNPN is available;
  • if the MS is not configured to use timer T3245, the MS maintains a list of SNPN-specific attempt counters for 3GPP access as specified in TS 24.501, and T3247 expires, then the MS removes for each SNPN-specific attempt counter for 3GPP access that has a value greater than zero and less than the MS implementation-specific maximum value the respective SNPN from the list of SNPNs for which the N1 mode capability was disabled, as specified in clause 5.3.20.3 in TS 24.501; and
  • the MS shall delete stored information on SNPNs for which the N1 mode capability was disabled when the MS is switched off, the USIM is removed, the entries of the "list of subscriber data" for the SNPNs are updated, or timer TJ expires.
If the MS does not support access to an SNPN using credentials from a credentials holder, the MS should maintain a list of SNPNs where the N1 mode capability was disabled because IMS voice was not available and the MS's usage setting was "voice centric". If the MS supports access to an SNPN using credentials from a credentials holder, the MS should maintain one or more lists of SNPNs where the N1 mode capability was disabled because IMS voice was not available and the MS's usage setting was "voice centric", each associated with selected entry of the "list of subscriber data" or the PLMN subscription. When the MS disables its N1 mode capability due to IMS voice not available and the MS's usage setting was "voice centric":
  • the MS should add the SNPN identity of the SNPN to the list of SNPNs where voice service was not possible in N1 mode and should start timer TK if timer TK is not already running. The number of SNPNs that the MS can store where voice services is not possible is implementation specific, but it shall be at least one. The value of timer TK is MS implementation specific;
  • in automatic SNPN selection the MS shall not consider SNPNs where voice service was not possible in N1 mode as SNPN selection candidates, unless no other SNPN is available; and
  • the MS shall delete stored information on SNPNs where voice service was not possible in N1 mode when the MS is switched off, the USIM is removed, the entries of the "list of subscriber data" for the SNPNs are updated, or timer TK expires.
The MS may support equivalent SNPNs. If the MS supports equivalent SNPNs, the ME shall store up to one list of equivalent SNPNs:
  • per entry of "list of subscriber data"; or
  • per the PLMN subscription, if the MS supports access to an SNPN using credentials from a credentials holder.
SNPNs in the list of equivalent SNPNs associated with the selected entry of "list of subscriber data" or the selected PLMN subscription shall be regarded by the MS as equivalent to each other for SNPN selection, cell selection, and cell re-selection. The list of equivalent SNPNs associated with the selected entry of "list of subscriber data" or the selected PLMN subscription is created, replaced or deleted at the end of each registration procedure. The stored list consists of a list of equivalent SNPNs as provided by the network plus the SNPN identity of the registered SNPN that provided the list. When the MS is switched off, the MS shall keep the stored list(s) so that they can be used for SNPN selection after switch on. The MS shall delete the stored list associated with an entry of "list of subscriber data" or the PLMN subscription, when the USIM is removed, the associated entry of "list of subscriber data" is updated, or the MS registered for emergency services deregisters.
Up

4.9.3.1  At switch-on or recovery from lack of coveragep. 64

4.9.3.1.0  Generalp. 64
At switch on, following recovery from lack of coverage, or when the MS starts operating in the SNPN access mode, the MS selects the registered SNPN or an equivalent SNPN (if it is available) using NG-RAN access technology and if necessary (in the case of recovery from lack of coverage, see clause 4.5.2) attempts to perform an LR.
If successful registration is achieved, the MS indicates the selected SNPN.
If there is no registered SNPN, or registration is not possible due to the SNPN and all equivalent SNPNs, if any, being unavailable or registration failure, unless the MS needs to select an SNPN for onboarding services in SNPN, the MS follows the procedure in clause 4.9.3.1.1 or clause 4.9.3.1.2 depending on its SNPN selection mode. If the MS needs to select an SNPN for onboarding services in SNPN, the MS follows the procedure in clause 4.9.3.1.3 or clause 4.9.3.1.4 depending on its SNPN selection mode for onboarding services in SNPN. At switch on, the MS shall use the SNPN selection mode and the SNPN selection mode for onboarding services in SNPN that were used before switching off.
If registration is not possible on recovery from lack of coverage due to the registered SNPN and all equivalent SNPNs, if any, being unavailable, an MS may, optionally, continue looking for the registered SNPN or an equivalent SNPN for an implementation dependent time.
Up
4.9.3.1.1  Automatic SNPN selection mode procedurep. 64
If:
  • there is at least one entry in the "list of subscriber data"; or
  • there is zero or more entries in the "list of subscriber data", the MS has a USIM with a PLMN subscription and the ME is provisioned with the SNPN selection parameters associated with the PLMN subscription,
the MS shall select one entry in the "list of subscriber data", if any, or the PLMN subscription, if any, to be used for automatic SNPN selection. How the MS selects the entry in the "list of subscriber data" or the PLMN subscription is MS implementation specific.
The MS selects an SNPN, if available and allowable, in the following order:
  1. the SNPN with which the UE was last registered or an equivalent SNPN;
  2. the SNPN identified by an SNPN identity of the subscribed SNPN in the selected entry of the "list of subscriber data" in the ME, if any;
  3. if the MS supports access to an SNPN using credentials from a credentials holder, using the SNPN selection parameters in the selected entry of the "list of subscriber data" or associated with the selected PLMN subscription:
    1. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which is identified by an SNPN identity contained in the user controlled prioritized list of preferred SNPNs (in priority order);
    2. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which is identified by an SNPN identity contained in the credentials holder controlled prioritized list of preferred SNPNs (in priority order);
    3. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which broadcast a GIN contained in the credentials holder controlled prioritized list of GINs (in priority order). If more than one such SNPN broadcast the same GIN, the order in which the MS attempts registration on those SNPNs is MS implementation specific; and
    4. each SNPN identified by an SNPN identity which is included neither in the SNPN selection parameters of the entries of the "list of subscriber data" nor in the SNPN selection parameters associated with the PLMN subscription, which does not broadcast a GIN which is included in the credentials holder controlled prioritized list of GINs, and which broadcasts an indication that the SNPN allows registration attempts from MSs that are not explicitly configured to select the SNPN. If more than one such SNPN is available, the order in which the MS attempts registration on those SNPNs is MS implementation specific.
The MS shall limit its search for the SNPN to the NG-RAN access technology.
Once the MS selects the SNPN, the MS attempts registrations on the selected SNPN using the NG-RAN access technology, the subscriber identifier and the credentials from the selected entry of the "list of subscriber data" or from the USIM, if the PLMN subscription is selected.
If successful registration is achieved, the MS indicates the selected SNPN.
If registration cannot be achieved because no SNPNs are available, allowable, and identified by an SNPN identity in an entry of the "list of subscriber data" in the ME, the MS indicates "no service" to the user, waits until a new SNPN is available, allowable, and identified by an SNPN identity in an entry of the "list of subscriber data" in the ME and then repeats the procedure.
If there were one or more SNPNs which were available, allowable, and identified by an SNPN identity in an entry of the "list of subscriber data" in the ME but an LR failure made registration on those SNPNs unsuccessful, the MS selects one of those SNPNs again and enters a limited service state.
If an SNPN is being removed from the "temporarily forbidden PLMNs" or the "permanently forbidden PLMNs" list (e.g due to MS implementation specific timer not shorter than 60 minutes expires or timer T3245 expires), and the MS is in limited service state, and the MS does not have a PDU session for emergency services, the MS shall perform SNPN selection as described in subclause 4.9.3.1. If the MS has an established emergency PDU session, then the UE shall attempt to perform the SNPN selection subsequently after the emergency PDU session is released.
Up
4.9.3.1.2  Manual SNPN selection mode procedurep. 65
The MS indicates to the user any available SNPNs which meet the criteria specified in bullets a) and b). If the MS does not support access to an SNPN using credentials from a credentials holder, this includes SNPNs in the list of "permanently forbidden SNPNs", and the list of "temporarily forbidden SNPNs". The MS may indicate to the user whether the available SNPNs are present in the list of "temporarily forbidden SNPNs" or the list of "permanently forbidden SNPNs". If the MS supports access to an SNPN using credentials from a credentials holder, this includes SNPNs in the lists of "permanently forbidden SNPNs", and the lists of "temporarily forbidden SNPNs" associated with each entry of the "list of subscriber data" or the PLMN subscription. The MS may indicate to the user whether the available SNPNs are present in a list of "temporarily forbidden SNPNs" or a list of "permanently forbidden SNPNs" for an entry of the "list of subscriber data" or the PLMN subscription.
  1. SNPNs identified by an SNPN identity in an entry of the "list of subscriber data" in the ME, if any. The order in which those SNPNs are indicated is MS implementation specific;
  2. if the MS supports access to an SNPN using credentials from a credentials holder, for the SNPNs which broadcast the indication that access using credentials from a credentials holder is supported:
    1. each SNPN which is identified by an SNPN identity contained in one of the user controlled prioritized lists of preferred SNPNs configured in the ME. SNPNs included in the same list are indicated in the order in which they are included in the list. Prioritization between the different lists is MS implementation specific;
    2. each SNPN which is identified by an SNPN identity contained in one of the credentials holder controlled prioritized lists of preferred SNPNs configured in the ME. SNPNs included in the same list are indicated in the order in which they are included in the list. Prioritization between the different lists is MS implementation specific;
    3. each SNPN which broadcasts a GIN contained in one of the credentials holder controlled prioritized lists of GINs configured in the ME. SNPNs broadcasting a GIN included in the same list are indicated in the order in which the GIN is included in the list. Prioritization between the different lists is MS implementation specific. If more than one SNPN broadcast the same GIN, the order in which those SNPNs are indicated is MS implementation specific; and
    4. each SNPN identified by an SNPN identity which is included neither in the SNPN selection parameters of the entries of the "list of subscriber data" nor in the SNPN selection parameters associated with the PLMN subscription and which does not broadcast a GIN which is included in one of the credentials holder controlled prioritized lists of GINs configured in the ME. The order in which those SNPNs are indicated is MS implementation specific.
For each of the SNPNs indicated to the user, the MS shall forward a human-readable network name along with the SNPN identity to the upper layers if the system information broadcasted for the SNPN includes the human-readable network name for the SNPN.
The MS shall limit its search for the SNPN to the NG-RAN access technology.
The user may select an SNPN and the MS then initiates registration on this SNPN using the NG-RAN access technology, the subscriber identifier and the credentials from the selected entry of the "list of subscriber data" or from USIM, if the PLMN subscription is selected, determined as follows:
  • for bullet a) above, the entry of the "list of subscriber data", with the SNPN identity matching the selected SNPN (this may take place at any time during the presentation of SNPNs), shall be considered as selected;
  • for bullet b-1) above:
    1. the entry of the "list of subscriber data" which contains the user controlled prioritized lists of preferred SNPNs that includes the SNPN identity of the selected SNPN shall be considered as selected, if the user controlled prioritized list of preferred SNPNs that includes the SNPN identity of the selected SNPN is included in the entry of the "list of subscriber data"; or
    2. the PLMN subscription shall be considered as selected, if the user controlled prioritized list of preferred SNPNs associated with the PLMN subscription includes the SNPN identity of the selected SNPN;
  • for bullet b-2) above:
    1. the entry of the "list of subscriber data" which contains the credentials holder controlled prioritized list of preferred SNPNs that includes the SNPN identity of the selected SNPN shall be considered as selected, if the credentials holder controlled prioritized list of preferred SNPNs that includes the SNPN identity of the selected SNPN is included in the entry of the "list of subscriber data"; or
    2. the PLMN subscription shall be considered as selected, if the credentials holder controlled prioritized list of preferred SNPNs associated with the PLMN subscription includes the SNPN identity of the selected SNPN;
  • for bullet b-3) above:
    1. the entry of the "list of subscriber data" which contains the credentials holder controlled prioritized list of GINs that includes the GIN broadcast by the selected SNPN shall be considered as selected, if the credentials holder controlled prioritized list of GINs that includes the GIN broadcast by the selected SNPN is included in the entry of the "list of subscriber data"; or
    2. the PLMN subscription shall be considered as selected, if the credentials holder controlled prioritized list of GINs associated with the PLMN subscription includes the GIN broadcast by the selected SNPN; and
  • for bullet b-4) above, the entry of the "list of subscriber data" or the PLMN subscription shall be selected by MS implementation specific means.
Once the MS has registered on an SNPN selected by the user, the MS shall not automatically register on a different SNPN unless:
  1. the user selects automatic SNPN selection mode;
  2. the user initiates an emergency call while the MS is in limited service state and either the SNPN does not broadcast the indication of support of emergency calls in limited service state or the registration request for emergency services is rejected by the network; or
  3. the new SNPN is declared as an equivalent SNPN by the registered SNPN.
If the user does not select an SNPN, the selected SNPN shall be the one that was selected either automatically or manually before the SNPN selection procedure started. If no such SNPN was selected or that SNPN is no longer available, then the MS shall attempt to camp on any acceptable cell and enter the limited service state.
Up
4.9.3.1.3  Automatic SNPN selection mode procedure for onboarding services in SNPN |R17|p. 67
When the MS needs to access an SNPN for onboarding services in SNPN, the MS shall select an SNPN indicating that onboarding is allowed and, if the onboarding SNPN selection information is pre-configured, also matching the onboarding SNPN selection information. If more than one such SNPNs are available, how the MS selects one of those SNPNs is MS implementation specific. The MS shall not select an SNPN not indicating that onboarding is allowed or not matching the onboarding SNPN selection information, if pre-configured, for onboarding services in SNPN.
The MS shall limit its search for the SNPN to the NG-RAN access technology.
Once the MS selects the SNPN, the MS shall attempt initial registration for onboarding services in SNPN on the selected SNPN using the NG-RAN access technology and the default UE credentials for primary authentication.
If successful registration is achieved, the MS may indicate to upper layers the selected SNPN. How this indication is displayed by upper layers is implementation specific.
If successful registration is not achieved and one or more other SNPNs indicating that onboarding is allowed and matching the onboarding SNPN selection information, if pre-configured, are available, the MS can select such other SNPN and attempt initial registration for onboarding services in SNPN on the selected SNPN using the NG-RAN access technology and the default UE credentials for primary authentication, or the MS can perform SNPN selection not for onboarding services in SNPN as specified in clause 4.9.3.1.1 or clause 4.9.3.1.2 depending on its SNPN selection mode.
If:
  • registration cannot be achieved because no SNPNs indicating that onboarding is allowed and matching the onboarding SNPN selection information, if pre-configured, are available; or
  • there were one or more SNPNs indicating that onboarding is allowed and matching the onboarding SNPN selection information, if pre-configured, but an LR failure made registration on all those SNPNs unsuccessful;
the MS can indicate no onboarding services to upper layers, enter limited service state and wait until a new SNPN indicating that onboarding is allowed and matching the onboarding SNPN selection information, if pre-configured, is available and then repeat the procedure, or the MS can perform SNPN selection not for onboarding services in SNPN as specified in clause 4.9.3.1.1 or clause 4.9.3.1.2 depending on its SNPN selection mode.
Up
4.9.3.1.4  Manual SNPN selection mode procedure for onboarding services in SNPN |R17|p. 68
The MS shall indicate to upper layers one or more SNPNs, which are available and indicate that onboarding is allowed.
These include SNPNs in the list of "permanently forbidden SNPNs" for onboarding services and the list of "temporarily forbidden SNPNs" for onboarding services. The MS may indicate to the user whether the available SNPNs are present in the list of "temporarily forbidden SNPNs" or the list of "permanently forbidden SNPNs".
The MS shall limit its search for the SNPN to the NG-RAN access technology.
For each SNPN indicated to upper layers, the MS shall indicate to the upper layers along with the SNPN identity:
  1. whether the SNPN matches the onboarding SNPN selection information, if pre-configured; and
  2. the human-readable network name, if the system information broadcast includes the human-readable network name for the SNPN.
Up

4.9.3.2  User reselectionp. 68

4.9.3.2.0  Generalp. 68
At any time the user may request the MS to initiate reselection and registration onto an available SNPN, according to the following procedures, dependent upon the SNPN selection mode of the UE.
4.9.3.2.1  Automatic SNPN selection modep. 68
If:
  • there is at least one entry in the "list of subscriber data"; or
  • there is zero or more entries in the "list of subscriber data", the MS has a USIM with a PLMN subscription and the ME is provisioned with the SNPN selection parameters associated with the PLMN subscription,
the MS shall select one entry in the "list of subscriber data", or the PLMN subscription, if any, to be used for automatic SNPN selection. How the MS selects the entry in the "list of subscriber data" or the PLMN subscription is MS implementation specific.
The MS selects an SNPNs, if available and allowable, in accordance with the following order:
  1. the SNPN identified by an SNPN identity of the subscribed SNPN in the selected entry of the "list of subscriber data" in the ME, if any, excluding the previously selected SNPN;
  2. if the MS supports access to an SNPN using credentials from a credentials holder, using the SNPN selection parameters in the selected entry of the "list of subscriber data" or associated with the selected PLMN subscription:
    1. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which is identified by an SNPN identity contained in the user controlled prioritized list of preferred SNPNs (in priority order), excluding the previously selected SNPN;
    2. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which is identified by an SNPN identity contained in the credentials holder controlled prioritized list of preferred SNPNs (in priority order), excluding the previously selected SNPN;
    3. each SNPN which broadcasts the indication that access using credentials from a credentials holder is supported and which broadcast a GIN contained in the credentials holder controlled prioritized list of GINs (in priority order), excluding the previously selected SNPN. If more than one such SNPN broadcast the same GIN, the order in which the MS attempts registration on those SNPNs is MS implementation specific; and
    4. each SNPN identified by an SNPN identity which is included neither in the SNPN selection parameters of the entries of the "list of subscriber data" nor in the SNPN selection parameters associated with the PLMN subscription and which broadcasts an indication that the SNPN allows registration attempts from MSs that are not explicitly configured to select the SNPN, excluding the previously selected SNPN. If more than one such SNPN is available, the order in which the MS attempts registration on those SNPNs is MS implementation specific.
  3. the previously selected SNPN.
The MS shall limit its search for the SNPN to the NG-RAN access technology.
The previously selected SNPN is the SNPN which the MS has selected prior to the start of the user reselection procedure.
The equivalent SNPNs list shall not be applied to the user reselection in automatic SNPN selection mode.
Once the MS selects an SNPN, if the selected SNPN is other than the previously selected SNPN, the MS attempts registrations on the selected SNPN using the NG-RAN access technology, the subscriber identifier and the credentials from the selected entry of the "list of subscriber data" or from the USIM, if the PLMN subscription is selected.
Up
4.9.3.2.2  Manual SNPN selection mode procedurep. 69
The manual SNPN selection mode procedure of clause 4.9.3.1.2 is followed.

4.9.4  Abnormal casesp. 69

If:
a)
the MS does not support access to an SNPN using credentials from a credentials holder and:
  1. the "list of subscriber data" is empty; or
  2. for each entry of the "list of subscriber data", such that an SNPN with the SNPN identity of the entry is available:
    1. there has been an authentication failure for the subscriber identifier of the entry on the SNPN; or
    2. the MS has received an "illegal ME" or "illegal UE" response to an LR request for the subscriber identifier of entry on the SNPN; or
b)
the MS supports access to an SNPN using credentials from a credentials holder and:
  1. the "list of subscriber data" is empty and:
    1. the MS is not provisioned with SNPN selection parameters associated with the PLMN subscription;
    2. the MS does not have a USIM; or
    3. both of the above; or
  2. for each entry of the "list of subscriber data", such that an SNPN with the SNPN identity of the subscribed SNPN of the entry is available:
    1. there has been an authentication failure for the subscriber identifier of the entry on the SNPN; or
    2. the MS has received an "illegal ME" or "illegal UE" response to an LR request for the subscriber identifier of entry on the SNPN;
    and:
    1. the MS is not provisioned with SNPN selection parameters associated with the PLMN subscription;
    2. the MS does not have a USIM; or
    3. both of the above;
  3. for each available SNPN which broadcasts an indication that access using credentials from a credentials holder is supported and:
    1. is identified by an SNPN identity contained in one of the user controlled prioritized lists of preferred SNPNs configured in the ME;
    2. is identified by an SNPN identity contained in one of the credentials holder controlled prioritized lists of preferred SNPNs configured in the ME;
    3. broadcasts a GIN contained in one of the credentials holder controlled prioritized lists of GINs configured in the ME; or
    4. is identified by an SNPN identity which is included neither in the SNPN selection parameters of the entries of the "list of subscriber data" nor in the SNPN selection parameters associated with the PLMN subscription, which does not broadcast a GIN which is included in one of the credentials holder controlled prioritized lists of GINs configured in the ME and which broadcasts an indication that the SNPN allows registration attempts from MSs that are not explicitly configured to select the SNPN;
    the following applies:
    1. there has been an authentication failure in the SNPN; or
    2. the MS has received an "illegal ME" or "illegal UE" response to an LR request from the SNPN;
then effectively there is no selected SNPN ("No SIM" state).
In these cases, the states of the cell selection process are such that the "list of subscriber data" (if any) or the PLMN subscription (if any) is not used. An MS in "No SIM" state configured with default UE credentials for primary authentication may perform SNPN selection procedure for onboarding services in SNPN. Except when an MS in "No SIM" state performs an initial registration for emergency services to an SNPN or an MS in "No SIM" state configured with default UE credentials for primary authentication performs registration for onboarding services in SNPN, no further attempts at registration on any SNPN are made until the MS is switched off and on again, or an entry of the "list of subscriber data" with the SNPN identity of the SNPN is updated or the USIM is inserted. When performing an initial registration for emergency services, an SNPN supporting emergency services, of the current serving cell is temporarily considered as the selected SNPN. If the MS needs to make an emergency call, the MS supports accessing a PLMN and there is no available SNPN supporting emergency services, the MS shall stop operating in SNPN access mode and attempt to camp on a cell of a PLMN so that emergency calls can be made. After an emergency call is released, the MS may re-start operating in SNPN access mode and perform SNPN selection.
When in automatic SNPN selection mode and the MS is in the "not updated" state with one or more suitable cells to camp on; then after the maximum allowed unsuccessful LR requests (controlled by the specific attempt counters) the MS may continue (or start if it is not running) the user reselection procedure in clause 4.9.3.2 1.
Up

Up   Top   ToC