3.2 Idle mode procedures and general procedures in packet idle and packet transfer modes

3GPP44.018GSM/EDGE Radio Resource Control (RRC) protocolMobile radio interface Layer 3 specificationRelease 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

3.2.1 Mobile Station side

In idle mode, the MS listens to the BCCH or EC-BCCH and to the paging sub-channel for the paging group the MS belongs to in idle mode (cf. 3GPP TS 43.013); it measures the radio propagation for connection with other cells.

In packet idle and packet transfer modes (applicable only to a GPRS mobile station) the mobile station listens to either the PBCCH, if that is present in the cell, or BCCH. The requirements for the monitoring of system information is further specified in 3GPP TS 45.008 [34]. An exception case is where a mobile station has enabled PEO or EC operation in which case the following applies:

– A MS that has enabled PEO shall monitor system information on the BCCH, when in packet idle mode, as described in sub-clause 3.9.

– A MS that has enabled EC operation shall monitor system information on the EC-BCCH, when in packet idle mode, as described in sub-clause 3.10.

Moreover, the mobile station measures the radio propagation for connection with other cells. A MS that has enabled PEO or EC operation shall only measure the radio propagation for connection with other cells when the serving cell is no longer determined to be suitable (see 3GPP TS 45.008 [34]).

A mobile station camping on the cell as a result of a cell change order or redirection from E-UTRAN to GERAN is not required to perform the complete acquisition of the system information of the cell on BCCH before proceeding with a RR connection establishment (see sub-clause 3.3).

The mobile station shall perform the acquisition on the BCCH of the cell of the following messages if not provided in the MobilityFromEUTRACommand or, respectively, in the E-UTRA RRCConnectionRelease message and the mobile station is not performing CS fallback (see 3GPP TS 36.331):

– SYSTEM INFORMATION TYPE 3,

– for a GPRS capable mobile station in a cell supporting GPRS, SYSTEM INFORMATION TYPE 13, and

– SYSTEM INFORMATION TYPE 1 if broadcast in the cell (see 3GPP TS 45.002).

The mobile station shall perform the acquisition on the BCCH of the cell of the following messages if not provided in the E-UTRA RRCConnectionRelease message and the mobile station is performing CS fallback (see 3GPP TS 36.331):

– SYSTEM INFORMATION TYPE 3,

– SYSTEM INFORMATION TYPE 1 if broadcast in the cell (see 3GPP TS 45.002).

If SYSTEM INFORMATION TYPE 3 and, for a GPRS capable mobile station in a cell supporting GPRS, SYSTEM INFORMATION TYPE 13 were received in the MobilityFromEUTRACommand message or in the E-UTRA RRCConnectionRelease message but SYSTEM INFORMATION TYPE 1 was not included, the mobile station shall assume that SYSTEM INFORMATION TYPE 1 is not broadcast in the cell.

In packet idle mode (applicable only to a GPRS mobile station ), a mobile station listens to the paging sub-channels on the PCCCH or CCCH. An exception case is where a mobile station has enabled PEO or EC operation in which case the following applies:

– A MS that has enabled PEO listens to its paging sub-channel (nominal paging group) on the CCCH as described in sub-clause 3.9.

– A mobile station that has enabled EC operation listens to its paging sub-channel (nominal paging group) on the EC-CCCH as described in sub-clause 3.10.

Paging sub-channels are monitored according to the paging group determined for the mobile station, its current discontinuous reception (DRX) mode and in case EC operation has been enabled, its current downlink Coverage Class. The determination of paging group for the mobile station is defined in 3GPP TS 45.002. The DRX procedures are defined in 3GPP TS 44.060 and 3GPP TS 45.002.

Mobile station support for reception of Earthquake and Tsunami Warning System (ETWS) Primary Notification messages is optional. In idle mode or in packet idle mode (applicable only to a GPRS mobile station), the mobile station may determine that an ETWS event has occurred (see sub-clause 3.2.2.3 and 9.1.22) in which case it shall leave DRX mode, start timer T3232, start reading all paging groups and attempt to acquire an ETWS Primary Notification message. The mobile station shall attempt to assemble all segments of the ETWS Primary Notification message, having the same Primary Notification Identifier (PNI) value, before delivering the complete message to the upper layers.

While attempting to acquire the ETWS Primary Notification message a mobile station shall continue to follow (packet) idle mode and connection establishment procedures. Upon initiating cell reselection or connection establishment procedures while attempting to acquire an ETWS Primary Notification message, a mobile station shall discard any partially received ETWS Primary Notification message and stop timer T3232. The mobile station shall not attempt to acquire an ETWS Primary Notification message while performing a connection establishment procedure or while performing cell reselection.

If the mobile station detects a change in the PNI value prior to acquiring a complete ETWS Primary Notification message, it shall abort the current message, restart timer T3232 and attempt to acquire the new message.

When the mobile station successfully acquires a complete ETWS Primary Notification message it shall stop timer T3232 and enter DRX mode. If timer T3232 expires the mobile station shall abort the current message and enter DRX mode.

A UTRAN capable mobile station in idle mode or packet idle mode attempts to read predefined configuration information from UTRAN Channels, as specified in 3GPP TS 45.008. This is only applicable to a mobile station supporting circuit-switched services.

Measurements are treated to assess the need of a cell change as specified in 3GPP TS 45.008. When the decision to change cells is made, the mobile station switches to the BCCH, PBCCH or EC-BCCH of the new cell. The broadcast information is then checked to verify the allowance to camp on this cell (cf. sub-clause 3.2.2). Dependent on the mobile station type and configuration, the mobile station may be required to try to read further BCCH or PBCCH or EC-BCCH information. If allowed, the cell change is confirmed, and the broadcast information is then treated for Mobility Management actions (cf. clause 4). Similarly, physical contexts are updated (list of neighbouring cells frequencies, thresholds for some actions, etc. (cf. 3GPP TS 45.008 and sub-clause 3.2.2)).

A mobile station configured for Extended Access Barring (EAB) shall read the SI3 Rest Octets IE in an attempt to determine if the SYSTEM INFORMATION TYPE 21 message is sent in the cell. If the SI3 Rest Octets IE does not provide this information the mobile station shall read the SI9 Rest Octets IE to make this determination (If SI 9 is sent):

– If the SYSTEM INFORMATION TYPE 21 message is sent the mobile station shall read it in an attempt to acquire EAB information (see sub-clause 10.5.2.37m).

– If the SYSTEM INFORMATION TYPE 21 message is not sent or is sent but does not include EAB information the mobile station shall consider EAB information it may have previously received to be invalid.

A mobile station that has enabled EC operation is not subject to Extended Access Barring (EAB) and shall instead use information sent in the EC SYSTEM INFORMATION TYPE 2 message and in the EC-SYSTEM INFORMATION type 4 message (if network sharing is supported in the cell) to determine the PLMN specific barring in effect for the serving cell. When attempting packet access it uses the PLMN specific barring and potentially the Implicit Reject Status (IRS) information sent using the EC-SCH INFORMATION message (see sub-clause 9.1.30c) to determine if packet access is allowed (see sub-clause 3.5.2a).

A mobile station supporting network sharing that has not enabled EC operation shall read the SYSTEM INFORMATION TYPE 3 message in an attempt to determine if the SYSTEM INFORMATION TYPE 22 message is sent in the cell:

– If the SYSTEM INFORMATION TYPE 22 message is sent the mobile station shall read it in an attempt to acquire network sharing information (see sub-clause 10.5.2.37n).

– If the SYSTEM INFORMATION TYPE 22 message is not sent or is sent but does not include network sharing information the mobile station shall consider network sharing as not supported in the cell and the network sharing information it may have previously received to be invalid.

A UTRAN and/or E-UTRAN capable mobile station supporting network sharing shall read the SYSTEM INFORMATION TYPE 22 message in an attempt to determine if the SYSTEM INFORMATION TYPE 23 message is sent in the cell:

– If the SYSTEM INFORMATION TYPE 23 message is sent the mobile station shall read it in an attempt to acquire UTRAN and/or E-UTRAN information for cell-reselection (as applicable) as described in sub-clause 10.5.2.37o.

– If the SYSTEM INFORMATION TYPE 23 message is sent but does not include UTRAN and/or E-UTRAN information for cell-reselection the mobile station shall consider UTRAN and/or E-UTRAN information for cell-reselection as not available in the cell and the previous information it may have received to be invalid.

– If the SYSTEM INFORMATION TYPE 23 message is not sent the mobile station shall acquire UTRAN and/or E-UTRAN information for cell-reselection from the SI2ter/SI2quater messages.

A mobile station that has enabled EC operation shall read the EC SYSTEM INFORMATION TYPE 3 message in an attempt to determine if the EC SYSTEM INFORMATION TYPE 4 message is sent in the cell:

– If the EC SYSTEM INFORMATION TYPE 4 message is sent the mobile station shall read it in an attempt to acquire network sharing information (see sub-clause 9.1.43s).

– If the EC SYSTEM INFORMATION TYPE 4 message is not sent or is sent but does not include network sharing information the mobile station shall consider network sharing as not supported in the cell and the network sharing information it may have previously received to be invalid.

3.2.2 Network side

3.2.2.1 System information broadcasting

SYSTEM INFORMATION TYPE 2 to 4 messages, and optionally TYPE 1, 2bis, 2ter, 7, 8, 13, 16 and 17 and further types are regularly broadcast by the network on the BCCH. Based on this information the mobile station is able to decide whether and how it may gain access to the system via the current cell. The SYSTEM INFORMATION TYPE 2bis message shall be sent if and only if the EXT-IND bit in the Neighbour Cell Description IE in both the TYPE 2 and TYPE 2bis messages indicates that each IE only carries part of the BA. SYSTEM INFORMATION TYPE 2ter message shall be sent if and only if this is indicated in SYSTEM INFORMATION TYPE 3 message.

A GSM 900 mobile station which only supports the primary GSM band P-GSM 900 (cf. 3GPP TS 45.005) may consider the EXT-IND bit in the Neighbour Cell Description IE in the SYSTEM INFORMATION TYPE 2 message as a spare bit. If it does so it shall assume that the information element carries the complete BA and it shall ignore any SYSTEM INFORMATION TYPE 2bis and 2ter messages.

SYSTEM INFORMATION TYPE 2quater messages may be sent to provide further information for Enhanced Measurement Report. It may also include UTRAN and/or E-UTRAN information for cell-reselection, measurement and reporting. A mobile station with no UTRAN capability should ignore 3G related information in this message. A mobile station with no E-UTRAN capability should ignore E-UTRAN related information in this message. SYSTEM INFORMATION TYPE 2quater message shall be sent if and only if this is indicated in SYSTEM INFORMATION TYPE 3 message.

The SI2 ter Rest Octet information element in the SI2ter message may provide information on UTRAN Cells and 3G Measurement Parameters. Information received in this message is only used for cell reselection in idle mode. The SYSTEM INFORMATION TYPE 2ter messages shall contain at least one 2G neighbouring cell description the ARFCN of which does not belong to the frequency band of the 2G neighbouring cells described in the SYSTEM INFORMATION TYPE 2 message.

When the SI2ter_MP_CHANGE_MARK parameter is changed in this information element, the MS shall re-read 3G Measurement parameters in all instances of SI2ter (by using SI2ter_INDEX and SI2ter_COUNT). When the SI2ter_3G_CHANGE_MARK is changed in this information element, the MS shall re-read UTRAN FDD Description and UTRAN TDD Description in all instances of SI2ter (by using SI2ter_INDEX and SI2ter_COUNT).

SYSTEM INFORMATION TYPE 2n messages may be sent to provide parameters affecting cell reselection for the neighbouring cells. SYSTEM INFORMATION TYPE 2n message shall be sent on BCCH (Ext) if and only if this is indicated in SYSTEM INFORMATION TYPE 13 message.

When the SI2n_CHANGE_MARK parameter is changed in this message, the MS shall re-read all the parameters in SI2n Rest Octets IE in a full set of SYSTEM INFORMATION 2n messages.

If the additional cell reselection parameters are broadcast then SYSTEM INFORMATION TYPE 3 message shall always contain these parameters. In addition to SYSTEM INFORMATION TYPE 3 at least either SYSTEM INFORMATION TYPE 4 or SYSTEM INFORMATION TYPE 7 and 8 messages shall contain these parameters too. SYSTEM INFORMATION TYPE 7 and 8 messages shall be sent if and only if this is indicated in SYSTEM INFORMATION TYPE 4 message.

SYSTEM INFORMATION TYPE 15 message is broadcast if dynamic ARFCN mapping is used in the PLMN. In this case ARFCN values are allocated and dynamically mapped to physical frequencies, see 3GPP TS 45.005. The presence of dynamic ARFCN mapping shall be indicated in Cell Options (BCCH) IE. When the value of the parameter DM_CHANGE_MARK is changed in the SYSTEM INFORMATION TYPE 15 message, the mobile station shall re-read information on dynamic mapping in a full set of SYSTEM INFORMATION 15 messages.

After the release of a dedicated connection, when returning to idle mode or packet idle mode, the mobile station may keep the dynamic ARFCN mapping information for the PLMN of the chosen cell under the following conditions:

– there has not been any handover during the connection; or

– the mobile station chooses the last cell (identified by the BCCH carrier and BSIC) that was used during the connection and there has not been any handover including dynamic ARFCN mapping information after reception of the dynamic ARFCN mapping information.

Otherwise, the mobile station shall acquire new dynamic ARFCN mapping information.

If additional SoLSA specific parameters are broadcast then SYSTEM INFORMATION TYPE 16 and 17 messages, shall always contain these parameters. In addition to SYSTEM INFORMATION TYPE 16 and 17 messages at least either SYSTEM INFORMATION TYPE 4 or SYSTEM INFORMATION TYPE 7 and 8 messages shall contain these SoLSA specific parameters too. SYSTEM INFORMATION TYPE 16 and 17 messages shall be sent if and only if this is indicated in SYSTEM INFORMATION TYPE 3 message. The SoLSA information of any SYSTEM INFORMATION message shall be the same.

The SYSTEM INFORMATION TYPE 18 and 20 messages are sent when non-GSM broadcast information must be transmitted. The scheduling and repetition rate of these messages is determined by the system operator and is indicated in SYSTEM INFORMATION TYPE 9 message. Mobile stations without non-GSM capabilities defined for SI 18 and SI 20 should ignore these messages. An MS with non-GSM capabilities shall decode and identify information related to the respective Non-GSM protocol by reading the Non-GSM Protocol Discriminator field.

The SYSTEM INFORMATION TYPE 21 message is broadcast by the network if Extended Access Barring is in use in the cell.

The SYSTEM INFORMATION TYPE 22 message shall be broadcast by the network if network sharing (with or without domain-specific access control) is in use in the cell. The presence of SI 22 messages shall be indicated in SI 3 message. Additionally, in this case, the network may broadcast the SYSTEM INFORMATION TYPE 23 message to provide PLMN-specific UTRAN and/or E-UTRAN information for cell re-selection. The presence of SI 23 messages shall be indicated in SI 22 message.

SYSTEM INFORMATION TYPE 19 messages shall be provided if COMPACT neighbour cells exist (see 3GPP TS 45.008). The presence of SI 19 messages shall be indicated in SI 9 message.

The support of GPRS shall be indicated in SYSTEM INFORMATION TYPE 3 message. In addition, the support of GPRS shall be indicated in either SYSTEM INFORMATION TYPE 4 or SYSTEM INFORMATION TYPE 7 and 8 messages. If GPRS is supported, SYSTEM INFORMATION TYPE 13 message shall be sent. SI 13 message shall not be sent if GPRS is not supported. Additional requirements for the broadcast of system information in a cell supporting GPRS are specified in 3GPP TS 44.060.

If EC-GSM-IoT is supported in the cell then EC SYSTEM INFORMATION TYPE 1, 2 and 3 messages are regularly broadcast by the network on the EC-BCCH. Based on this information a mobile station that has enabled EC operation able to decide whether and how it may gain access to the system via the current cell.

EC SYSTEM INFORMATION TYPE 4 message is optionally broadcast by the network if EC-GSM-IoT and network sharing is supported in the cell. The presence of EC SYSTEM INFORMATION TYPE 4 message shall be indicated in the EC SYSTEM INFORMATION TYPE 3 message.

NOTE 1: The allowed scheduling of SYSTEM INFORMATION messages on the BCCH and EC SYSTEM INFORMATION messages on the EC-BCCH are specified in 3GPP TS 45.002.

NOTE 2: The network should take into account limitations of certain mobile stations to understand SYSTEM INFORMATION TYPE 2bis, TYPE 2ter, the EXT-IND bit in the Neighbour Cell Description, the indication of 2ter in SYSTEM INFORMATION TYPE 3 and formats used in the Neighbour Cell Description IE and Cell Channel Description IE used in SYSTEM INFORMATION messages, see this sub-clause, sub-clause 10.5.2.1b, and sub-clause 10.5.2.22.

NOTE 3: The network should take into account the limitations of earlier versions of mobile equipment to understand the 3-digit MNC format of the location area identification, see sub-clause 10.5.1.3.

The information broadcast may be grouped in the following classes:

– information giving unique identification of the current network, location area and cell;

– information used for candidate cell measurements for handover and cell selection procedures;

– information describing the current control channel structure;

– information controlling the random access channel utilization;

– information defining different options supported within the cell; and

– information about the length of the part of the message belonging to the phase 1 protocol.

The network may send to the mobile station BCCH scheduling information as specified below:

1) The BCCH scheduling information may be contained in the SYSTEM INFORMATION TYPE 9 messages. If so, SYSTEM INFORMATION TYPE 3 specifies where to find SYSTEM INFORMATION TYPE 9 messages carrying BCCH scheduling information.

2) If the mobile station has received BCCH scheduling information, it shall assume that this BCCH scheduling information is valid in the location area until new scheduling information is received. It may store the information in the ME and assume its validity after switch on in the same location area.

3) The network need not indicate the schedule of all SYSTEM INFORMATION messages in SYSTEM INFORMATION 9. For any System Information message, the MS shall monitor all blocks specified in 3GPP TS 45.002 for that System Information message and all blocks specified in the SYSTEM INFORMATION TYPE 9 message for that System Information message.

4) When the mobile station detects that the BCCH information is not scheduled as defined in the last received SI 9 message, it shall read the SYSTEM INFORMATION TYPE 3 message. If presence of BCCH scheduling information in SYSTEM INFORMATION TYPE 9 message is indicated, it shall try to read the information and continue as in 2 above. If presence of BCCH scheduling information in SYSTEM INFORMATION TYPE 9 message is not indicated, it shall assume that there is no valid BCCH scheduling information.

3.2.2.2 Paging

The network is required to send valid layer 3 messages continuously on all paging subchannels on CCCH.

3.2.2.3 Sending of ETWS Primary Notification

The network initiates the delivery of an ETWS Primary Notification message (see 3GPP TS 23.041) by broadcasting the PAGING REQUEST TYPE 1 message on all paging subchannels on CCCH with the ETWS Primary Notification field present within the P1 Rest Octets IE. These paging messages are sent continuously during the ETWS warning period.

Each paging message carries a segment of the actual ETWS Primary Notification message, i.e. segmentation is applicable if an ETWS Primary Notification message is too large to fit into the P1 Rest Octets of a single PAGING REQUEST TYPE 1 message. In order to allow a mobile station to receive the segments in any order, the size of a specific segment (retransmitted during the ETWS warning period) shall not be altered. Segments belonging to the same ETWS Primary Notification message shall be given the same Primary Notification Identifier (PNI) value.

3.2.3 Inter-RAT cell re-selection based on priority information

3.2.3.1 General

The network may provide priority information to enable priority-based cell reselection (see 3GPP TS 45.008). Inter-RAT cell reselection based on priority information applies only in case of autonomous cell reselection.

Two sets of priorities are defined for inter-RAT cell re-selection based on priority information: common priorities (see sub-clause 3.2.3.2) and individual priorities (see sub-clause 3.2.3.3). The mobile station shall delete all priorities when switched off.

While providing common or individual priorities, the network shall ensure that the GERAN priority value is different from all E-UTRAN priority values and from all UTRAN priority values, and that all UTRAN priority values are different from all E-UTRAN priority values. In addition, if for some E-UTRAN frequencies THRESH_E-UTRAN_high_Q is provided in the Enhanced Cell Reselection Parameters Description IE in the SI2quater message or, if network sharing is supported by the network (see sub-clause 3.8), in the SI23 message, the network shall ensure that the priority value for any frequency for which THRESH_E-UTRAN_high_Q is provided is different from the priority value for all frequencies for which THRESH_E-UTRAN_high_Q is not provided.

The mobile station shall determine each set, considering only individual priorities (respectively common priorities) when building the set of individual (respectively common) priorities. The mobile station shall perform the following steps, in the specified order:

– If the same priority value is assigned to GERAN and to one or more UTRAN or E-UTRAN frequencies then all such UTRAN and E-UTRAN priority values are considered as not in the set of priorities.

– If the same priority value is assigned to one or more UTRAN frequencies and one or more E-UTRAN frequencies, then all such priority values are considered as not in the set of priorities.

– If the same priority value is assigned to one or more E-UTRAN frequencies for which THRESH_E-UTRAN_high_Q is provided and one or more E-UTRAN frequencies for which THRESH_E-UTRAN_high_Q is not provided then all such priority values are considered as not in the set of priorities.

NOTE 1: These steps mean that if, for example, there are two UTRAN priority values, one E-UTRAN priority value (for a frequency for which THRESH_E-UTRAN_high_Q is provided) and one E-UTRAN priority value (for a frequency for which THRESH_E-UTRAN_high_Q is not provided) that are all the same, then all four priority values are considered as not in the set of priorities.

A set of individual priorities is valid if it contains at least one priority.

A set of common priorities is valid if both of the following conditions are met:

– The set of priorities includes a priority for GERAN;

– The mobile station does not have a valid set of individual priorities.

If the mobile station has a valid set of priorities, the priorities in this set shall be used for priority-based reselection as specified in 3GPP TS 45.008.

NOTE 2: It is possible that individual priorities inherited from UTRAN or E-UTRAN (see sub-clause 3.2.3.3) do not contain a priority for GERAN.

3.2.3.2 Common priorities information

A mobile station may receive common priorities information in the Priority and E-UTRAN Parameters Description IE in the SYSTEM INFORMATION TYPE 2quater message.

A mobile station supporting network sharing may receive PLMN specific UTRAN and E-UTRAN common priorities in the SYSTEM INFORMATION TYPE 23 message. If the SYSTEM INFORMATION TYPE 23 message is broadcast in the cell, a mobile station supporting network sharing shall use only UTRAN and E-UTRAN common priorities if provided in this message.

3.2.3.3 Provision of individual priorities information

A mobile station shall store individual priorities information if received in the Individual Priorities IE in the CHANNEL RELEASE message, PACKET MEASUREMENT ORDER message or in the PACKET CELL CHANGE ORDER message (see 3GPP TS 44.060). If received in a PACKET CELL CHANGE ORDER message, the mobile station shall use the parameters provided in the Individual Priorities IE only upon successful completion of the network controlled cell reselection procedure as described in 3GPP TS 44.060.

If the T3230 timeout value is provided the mobile station shall set timer T3230 to the value received and start timer T3230 (or restart timer T3230 with the timeout value provided if already running).

If the Individual Priorities IE contains priorities for more than 16 UTRAN FDD frequencies, more than 16 UTRAN TDD frequencies, or more than 8 E-UTRAN frequencies, then the mobile station may ignore the contents of the Individual Priorities IE and, in this case, shall delete any stored individual priorities.

NOTE: Each signalled frequency is counted whether or not the mobile station supports that frequency.

Stored individual priorities shall be deleted by the mobile station when any of the following occurs:

– a PLMN selection is performed and results in a change of PLMN and the new PLMNis not an equivalent PLMN, see 3GPP TS 23.122; or

– the mobile station is switched off; or

– a CHANNEL RELEASE message, PACKET MEASUREMENT ORDER message or PACKET CELL CHANGE ORDER is received with an indication that the individual priorities shall be deleted; or

– new individual priorities are received ; or

– timer T3230 expires.

At inter-RAT cell reselection from UTRAN or E-UTRAN to GERAN or cell selection or handover that results in a change of RAT from UTRAN or E-UTRAN to GERAN, the MS shall inherit individual priority information if the corresponding timer (T320 if the last serving RAT was E-UTRA; T322 if the last serving RAT was UTRA) has not expired. In this case the mobile station shall start timer T3230 with the timeout value set to the remaining validity time of the corresponding timer from the source RAT. If this inherited individual priority information includes more than one individual priority for GERAN frequencies, then the mobile station shall apply only the one applicable to the BCCH carrier of the first serving GERAN cell after the change of RAT as the individual priority for all GERAN cells for as long as the mobile station remains in GERAN. In this case the mobile station shall not apply the other GERAN individual priority(ies) until the MS leaves GERAN (see 3GPP TS 25.331, 3GPP TS 36.331).

NOTE: The network may provide individual priorities information for inter-RAT frequencies not configured by system information.