IP Address and Domain Name Facts | Generated by AI
Question: Which of the following statements about IP addresses and domain names are correct?
A. IP addresses are represented by numbers, while domain names are represented by characters
B. IP addresses are globally unique communication addresses
C. IP addresses and domain names have a one-to-one correspondence
D. Domain names can have more than three levels
E. Both IP addresses and domain names are limited to 32 bits
Answer:
The correct options are A, B, D.
Explanation of each option:
-
A. Correct
IP addresses (e.g., IPv4: 192.168.1.1) are numeric, while domain names (e.g., www.example.com) use human-readable characters/letters. -
B. Correct
IP addresses are globally unique identifiers used by devices to communicate on the internet (assuming no NAT/private addressing is hiding multiple devices behind one public IP). In the context of public internet routing, each public IP must be unique worldwide. - C. Incorrect
The relationship is many-to-one, not strictly one-to-one:- Multiple domain names (or subdomains) can point to the same IP (e.g., example.com and www.example.com often resolve to the same IP).
- One domain name can resolve to multiple IPs (round-robin DNS, CDNs like Cloudflare/Google).
Thus, there is no one-to-one correspondence.
- D. Correct
Domain names can have many levels. Examples:- www.mail.dept.university.country.example.com (6+ levels)
- sub.sub.sub.example.co.uk
The DNS hierarchy supports essentially unlimited depth (though practical limits exist due to the 255-character total length limit per fully qualified domain name).
- E. Incorrect
Only IPv4 addresses are 32 bits (4 octets).
Domain names are strings of characters (labels separated by dots), not fixed-length bit fields. They have no 32-bit restriction.
Additionally, IPv6 addresses are 128 bits, further proving the statement is wrong.
Summary
Correct: A, B, D
Incorrect: C (many-to-many possible), E (domains have no bit limit)
This question tests understanding of DNS fundamentals and common misconceptions about the IP–domain mapping.