Dears, I have to investigate model of ENUM trial in countries for my report relating to the preparation for ENUM trial in Vietnam. However I'm strucking with a question that i can not clear. Pls help me. These trial use existing telephone number in the country numbering plan for the trial. In Japan, 050 (IP Telephony), mobile number range, geographic telephone number, ext... are used. However, i could not find information to clear my question as follow: If the service provider doen't participate in the trial, then could their delegated number range be used for ENUM trial ? For example Provider A was delegated 0AB-CDEF-GHJK number range. But Proviser A did not participate in the ENUM trial. Can their subcribers used the number belonging to this range to register ENUM. How can services be provided to ENUM user with this number. In this case, could this number range be used in ENUM service ? Pls help me to clarify this. Any more information is very useful for me. Thanks & best regards. Thu Thuy.