3GPP51.010-1Mobile Station (MS) conformance specificationPart 1: Conformance specificationTS
While camped on a cell of the selected PLMN the MS may need to select a different cell in order to fulfil the normal service state. This ensures that the MS is camped on a cell from which it can reliably decode downlink data and with which it has a high probability of communications on the uplink.
The MS looks for suitable neighbour cells which satisfies 4 constraints including that It should not be in an LA which is in the list of "forbidden LAs for roaming".
20.18.2 Conformance requirement
1. To prevent repeated attempts to have roaming service on a not allowed LA, when the MS is informed that an LA is forbidden, the LA is added to a list of "forbidden LAs for roaming" which is stored in the MS, 3GPP TS 03.22; subclause 3.1.
2. If the MS has received the cause "Roaming not allowed in this LA", in response to a LU attempt, the Network Selection Procedure shall be started, 3GPP TS 03.22; subclause 4.3.3 L3, 3GPP TS 04.08 / 3GPP TS 24.008, subclause 18.104.22.168.
3. The MS can only perform camping on a suitable cell, which:
– should not be in an LA which is in the list of "forbidden LAs for roaming" 3GPP TS 03.22, subclause 3.2.1.
NOTE: LA stands for "Location Area" and LU stands for "Location Update".
20.18.3 Test purpose
1. To verify that if an LU is rejected with cause "Roaming not allowed in this LA", that the LAI of that cell is written into a forbidden list which prevents the MS from camping onto any cell in that LA.
2. To verify that if the MS has received the cause "Roaming not allowed in this LA", in response to a LU attempt, the Network Selection Procedure is initiated. This is verified indirectly by test purpose 3, in that the new LA is accessed as part of cell selection, hence CRH is disregarded.
3. To verify that if an LU is rejected, when attempting LU in a LA with LAI = LAI1, with cause "Roaming not allowed in this LA" and only cells of the selected PLMN are available, the MS will only camp and attempt LU in any LA with LAI <> LAI1.
20.18.4 Method of test
22.214.171.124 Initial conditions
Parameters changed from Default values table 20.1.
RF Signal Level
(dBV emf() / dBm)
63 / -50
53 / -60
RXLEV_ACCESS_MIN (dBV emf() / dBm)
23 / -90
23 / -90
MNC <> HPLMN
MNC <> HPLMN
MCC of HPLMN
MCC of HPLMN
a) The MS is switched on. Idle paging is sent on all carriers.
b) The SS monitors all RA requests from MS on carriers 1 and 2.
c) When the MS performs an IMSI attach onto carrier 1, the SS shall reject it with cause "Roaming not allowed in this LA".
d) The SS shall accept any LU on carrier 2.
e) The SS monitors all RA requests from MS on carriers 1 to 2.
20.18.5 Test requirements
1) The MS should respond on carrier 1 within 33 s of switch on.
2) After LU reject, the MS shall initiate the Network Selection Procedure and access onto Carrier 2 as part of cell selection within 33 s from returning to idle mode after the LU reject.
NOTE: The timing requirement in b) is given only for testing purposes only. No timing requirements are defined for the Network Selection Procedure, but the time allowed for cell selection (see 20.1) should be adequate.
3) After the LU reject on carrier 1, there shall be no more access attempts on this carrier.