Microsoft Networking Essentials Exam Microsoft Networking Essentials 3 — Questions and Answers
Question 1: A user reports they can ping 127.0.0.1 but cannot ping their default gateway. What does this most likely indicate?
- The TCP/IP stack is corrupt
- The network cable or physical layer connection has a problem (Correct answer)
- DNS is not resolving names
- The firewall is blocking ICMP entirely
Correct answer: The network cable or physical layer connection has a problem
Successfully pinging 127.0.0.1 confirms the local TCP/IP stack is functional, so the failure to reach the gateway points to a physical connectivity issue such as a bad cable or disconnected switch port.
Question 2: What is the valid host range for the subnet 10.0.4.0/22?
- 10.0.4.1 – 10.0.4.254
- 10.0.4.1 – 10.0.7.254 (Correct answer)
- 10.0.0.1 – 10.0.7.254
- 10.0.4.1 – 10.0.5.254
Correct answer: 10.0.4.1 – 10.0.7.254
A /22 mask covers 4 Class C blocks; 10.0.4.0/22 spans 10.0.4.0 – 10.0.7.255, so valid hosts are 10.0.4.1 through 10.0.7.254.
Question 3: Which IEEE standard defines the specifications for wireless LAN (Wi-Fi) networking?
- IEEE 802.3
- IEEE 802.11 (Correct answer)
- IEEE 802.1Q
- IEEE 802.5
Correct answer: IEEE 802.11
IEEE 802.11 is the standard family that defines wireless LAN (Wi-Fi) communications, including variants like 802.11n, 802.11ac, and 802.11ax.
Question 4: What Windows tool can be used to view and clear the ARP cache?
- nslookup
- arp -a / arp -d (Correct answer)
- netstat -r
- tracert
Correct answer: arp -a / arp -d
The arp command with -a displays the ARP cache and -d deletes entries, allowing administrators to view and clear IP-to-MAC mappings.
Question 5: Which protocol is used to automatically assign IP addresses to clients on a network?
- DNS
- DHCP (Correct answer)
- WINS
- NAT
Correct answer: DHCP
DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses, subnet masks, default gateways, and DNS server addresses to network clients.
Question 6: In a VLAN-tagged network, what does the 802.1Q tag inserted into an Ethernet frame contain?
- Source and destination MAC addresses
- The VLAN ID and priority bits (Correct answer)
- The IP checksum and TTL value
- Encryption keys for the frame payload
Correct answer: The VLAN ID and priority bits
The 802.1Q tag adds a 4-byte header to the Ethernet frame containing the 12-bit VLAN ID (0–4094) and 3-bit priority (CoS) bits.
Question 7: Which network device operates at Layer 3 and makes forwarding decisions based on IP addresses?
- Hub
- Switch
- Router (Correct answer)
- Bridge
Correct answer: Router
A router operates at Layer 3 (Network layer) and uses IP routing tables to forward packets between different networks based on destination IP addresses.
Microsoft Networking Essentials Exam Microsoft Networking Essentials 3
A user reports they can ping 127.0.0.1 but cannot ping their default gateway.
What does this most likely indicate?