When your computer wants to know the IPv4 address for isc.sans.org, which DNS Resource Record type is being requested?

When your computer wants to know the IPv4 address for isc.sans.org, which DNS Resource Record type is being requested?

• A. AAAA Record
• B. MX Record
• C. NS Record
• D. A Record

Answer: (D)

When a computer wants to determine the IPv4 address for a domain name like isc.sans.org, it requests information from the Domain Name System (DNS) using a specific type of resource record. The correct choice here is the A Record. An A Record (Address Record) maps a domain name to its corresponding IPv4 address. This is essential for the functionality of the internet, as it enables devices to locate and communicate with servers by resolving human-readable domain names into machine-readable IP addresses. When a user types in a URL, the A Record is the first step in translating that URL into an address that can be used to connect to the intended server. In contrast, the other types of records serve different purposes. An AAAA Record is for mapping domain names to IPv6 addresses, which is not applicable here since we are specifically looking for an IPv4 address. An MX Record is used to specify mail exchange servers for handling email for a domain, and a NS Record identifies the authoritative name servers for a domain zone, which helps in directing DNS queries but does not provide an actual IP address. Thus, the A Record is the appropriate DNS resource record type for translating a domain name into its IPv4 address.

When a computer wants to determine the IPv4 address for a domain name like isc.sans.org, it requests information from the Domain Name System (DNS) using a specific type of resource record. The correct choice here is the A Record.

An A Record (Address Record) maps a domain name to its corresponding IPv4 address. This is essential for the functionality of the internet, as it enables devices to locate and communicate with servers by resolving human-readable domain names into machine-readable IP addresses. When a user types in a URL, the A Record is the first step in translating that URL into an address that can be used to connect to the intended server.

In contrast, the other types of records serve different purposes. An AAAA Record is for mapping domain names to IPv6 addresses, which is not applicable here since we are specifically looking for an IPv4 address. An MX Record is used to specify mail exchange servers for handling email for a domain, and a NS Record identifies the authoritative name servers for a domain zone, which helps in directing DNS queries but does not provide an actual IP address.

Thus, the A Record is the appropriate DNS resource record type for translating a domain name into its IPv4 address.