The DNS maps the IP address to

2015

The DNS maps the IP address to

  1. A.

    A binary address as strings

  2. B.

    An alphanumeric address

  3. C.

    A hierarchy of domain names

  4. D.

    A hexadecimal address

Attempted by 394 students.

Show answer & explanation

Correct answer: C

Concept

The Domain Name System (DNS) is the Internet's distributed naming service. Its job is to translate between numeric IP addresses and human-readable domain names, where those domain names are organised as an inverted tree, a hierarchy that runs from the root down through top-level domains, second-level domains and host names.

Application

A bare IP address such as 203.0.113.10 carries no meaning for a person, so DNS associates it with a structured, hierarchical domain name such as www.example.com. Reading the name right to left moves down the hierarchy: the root, then the top-level domain .com, then example, then the host www. This naming tree is exactly what an IP address is mapped to.

Cross-check

Forward lookup turns a domain name into an IP address; reverse lookup turns an IP address back into a domain name (IPv4 addresses use the IN-ADDR.ARPA tree and IPv6 addresses use the IP6.ARPA tree). In both directions the human-facing side of the mapping is the hierarchy of domain names, confirming the result.

A video solution is available for this question — log in and enroll to watch it.

Explore the full course: Isro