Which database provides official address assignments including IPv4, IPv6, and AS numbers?

• A. Whois Database
• B. DNS Zone File
• C. Routing Table
• D. ARP Cache

Answer: (A)

Understanding who owns and is allocated IP blocks and Autonomous System numbers is essential for accurate resource tracking and routing decisions. The database that records these official address assignments is the Whois database, managed by the regional internet registries (ARIN, RIPE, APNIC, LACNIC, AfriNIC). A Whois record shows who holds an IPv4 or IPv6 allocation and which organization owns an autonomous system number, along with contact and administrative details. This makes Whois the authoritative source for current ownership and allocation status of IP resources. In contrast, a DNS Zone File maps domain names to IP addresses, a Routing Table lists prefixes and next-hop information used by routers, and an ARP Cache contains local IP-to-MAC mappings, not official allocation data.