Which distributed database allows hostnames lo be mapped to IP addresses?

The Domain Name System (DNS) is a foundational protocol for the internet that functions as a global, hierarchical, and distributed database. Its primary purpose is to translate human-friendly hostnames (e.g., www.cisco.com) into the numerical IP addresses (e.g., 72.163.4.185) required for locating and identifying computer services and devices with the underlying network protocols. This distributed nature ensures scalability and resilience, as the database is spread across many servers worldwide rather than being stored in a single location.

A. Dynamic Host Configuration Protocol (DHCP) automatically assigns IP addresses and network configuration parameters to clients, but it is not a distributed database for name resolution.
B. Network Time Protocol (NTP) is a protocol designed specifically for synchronizing the clocks of computer systems over a network.
D. Cisco Discovery Protocol is a proprietary Layer 2 protocol used by Cisco devices to share information with other directly connected Cisco equipment.

1. Cisco Official Documentation: In the IP Addressing: DNS Configuration Guide, Cisco IOS XE Gibraltar 16.12.x, the section "Information About DNS" states, "The Domain Name System (DNS) is a distributed database in which you can map hostnames to IP addresses through a hierarchy of domain names."

2. Internet Engineering Task Force (IETF) Standard: RFC 1034, Domain Names - Concepts and Facilities, Section 2.1, "Underlying Assumptions," describes the system's requirements: "The database is distributed." The introduction further clarifies its role in mapping domain names to host addresses.

3. University Courseware: MIT OpenCourseWare, 6.033 Computer System Engineering, Spring 2018, Lecture 17 notes on "Naming," describes DNS as a "hierarchical, distributed database for names" that primarily resolves names to IP addresses.