NewDelhi : The problem behind the Mobile Number portability all over the country is going to be changed. The STD dialing pattern was the main problem behind the MNP. Earlier We can only use 91 or zero for dialing STD.But all system has going to be changed and will call absence of zero and 91 from this July Onwards, which is used to simplify the STD calling systems... . Its is very useful to the people who migrate from one state to other state for studies and job purpose, hence they can use same number by without changing and port with any network as by wish. The popular netwrorks like airtel ,vodafone has already used this system. By coming July all other network opertors will become under this service