CIW Internet Protocols & Network Foundations 1 — Questions and Answers
Question 1: At which layer of the OSI model does the IP protocol operate?
- Physical
- Data Link
- Network (Correct answer)
- Transport
Correct answer: Network
IP operates at Layer 3 (Network layer), responsible for logical addressing and routing packets between networks.
Question 2: Which port does HTTP use by default?
- 21
- 25
- 80 (Correct answer)
- 443
Correct answer: 80
HTTP uses port 80 by default for unencrypted web traffic, while HTTPS uses port 443.
Question 3: What is the primary difference between TCP and UDP?
- TCP is faster but less reliable than UDP
- UDP provides guaranteed delivery while TCP does not
- TCP provides guaranteed, connection-oriented delivery while UDP does not (Correct answer)
- UDP is connection-oriented while TCP is connectionless
Correct answer: TCP provides guaranteed, connection-oriented delivery while UDP does not
TCP is connection-oriented and guarantees reliable, ordered delivery through acknowledgments; UDP is connectionless and offers no delivery guarantee.
Question 4: Which protocol is responsible for automatically assigning IP addresses to devices on a network?
- DNS
- DHCP (Correct answer)
- FTP
- SNMP
Correct answer: DHCP
DHCP (Dynamic Host Configuration Protocol) automatically leases IP addresses, subnet masks, gateways, and DNS server addresses to network clients.
Question 5: What is the purpose of the ARP (Address Resolution Protocol)?
- Assigns IP addresses to domain names
- Maps IP addresses to MAC addresses (Correct answer)
- Routes packets between different networks
- Encrypts network traffic between endpoints
Correct answer: Maps IP addresses to MAC addresses
ARP resolves a known IP address to its corresponding MAC (hardware) address on a local network segment.
Question 6: Which protocol is used by an email client to send messages to a mail server?
- POP3
- IMAP
- SMTP (Correct answer)
- FTP
Correct answer: SMTP
SMTP (Simple Mail Transfer Protocol) is the standard protocol for sending and relaying email messages between clients and servers.
Question 7: What does a TTL (Time to Live) value in an IP packet control?
- How long a DNS record is cached
- The maximum number of hops a packet can traverse before being discarded (Correct answer)
- The duration a TCP connection stays open
- The timeout period for an HTTP request
Correct answer: The maximum number of hops a packet can traverse before being discarded
The IP TTL field is decremented by each router; when it reaches zero, the packet is discarded, preventing packets from circulating indefinitely.
CIW Internet Protocols & Network Foundations 1
At which layer of the OSI model does the IP protocol operate?