Numbering plan for public data networks. ITU-T Recommendation X.121 describes the format of data network identification codes (DNIC). All DNICs consist of four digits. The first three digits identify a country; this is the data country code (DCC). The fourth digit enables identification of a network specific in the country.
Technical prescriptions
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- SR 784.101.113/2.4 Numbering plan x.121
Last modification 26.07.2022
