Data Network Identification Code is the same three digits as used in the Data Network Identification Code has three digits to identify the country, (one to identify a zone and two to identify the country within the zone) and one to identify the PDN (allowing only ten in each country).
Data Network Identification Code is intended to identify and permit automated switching of data traffic to particular networks.
Data Network Identification Code in the United States these are assigned by the Federal Communications Commission (FCC).