This ETSI Technical Report (ETR) clarifies recommended measures which may be adopted by the GSM infrastructure to enable interworking to be obtained between the GSM infrastructure and various Mobile Station (MS implementations of the GSM Phase 1 standard. The objective is to obtai compatibility without changing the consolidated set of Phase 1 specifications. This ETR describes the recommended changes to the infrastructure to cater for specific faults within some Phase 1 MSs. The lifetime of the herein described measures together with their potential impact on optimal network performance is out of the scope of this ETR
