CompTIA Updated N10-009 Exam Questions and Answers by moshe

Understanding Subnetting:

The subnet mask 255.255.255.240 (or /28) indicates that each subnet has 16 IP addresses (14 usable addresses, 1 network address, and 1 broadcast address).

Calculating the Subnet Range:

Subnet Calculation: For the IP address 10.0.0.95 with a /28 subnet mask:

Network address: 10.0.0.80

Usable IP range: 10.0.0.81 to 10.0.0.94

Broadcast address: 10.0.0.95

Router Interface Configuration:

Broadcast Address Issue: The IP address 10.0.0.95 is the broadcast address for the subnet 10.0.0.80/28. Configuring a router interface with the broadcast address will cause routing issues as it is not a valid host address.

Comparison with Other Options:

The web server is in a different subnet: The web server (10.0.0.81) is within the same subnet range (10.0.0.80/28).

The IP address space is a class A network: While 10.0.0.0 is a Class A network, this does not explain the routing issue caused by the broadcast address.

The subnet is in a private address space: The private address space designation (RFC 1918) does not impact the routing issue related to the broadcast address configuration.

Resolution:

Reconfigure the router interface with a valid host IP address within the usable range, such as 10.0.0.94.

To monitor server availability, SNMP traps are the best choice. SNMP (Simple Network Management Protocol) allows devices to send alerts (traps) when certain conditions are met, such as server downtime or high resource usage.

Breakdown of Options:

A. Packet capture – Capturing packets provides insights into network traffic but does not actively monitor server availability.

B. Data usage reports – These analyze network traffic consumption but do not indicate whether a server is available or not.

C. SNMP traps – Correct answer. SNMP traps notify administrators of server issues in real time.

D. Configuration monitoring – This tracks configuration changes rather than availability.

Border Gateway Protocol (BGP) is the primary protocol used to route traffic on the public internet. It allows ISPs and large networks to exchange routing information, making it an Exterior Gateway Protocol (EGP).

Breakdown of Options:

A. BGP – Correct answer. Used for internet routing and exchanges routing information between ISPs.

B. OSPF – An Interior Gateway Protocol (IGP) used for routing within an autonomous system (not the public internet).

C. EIGRP – Cisco’s proprietary IGP, used within private networks, not the public internet.

D. RIP – An older distance-vector protocol, not scalable for the internet.

WPA3-Enterprise provides strong security and supports authentication using domain identities through a RADIUS server and 802.1X authentication. This is the best choice for a corporate environment requiring user-based authentication.

WPA3-Enterprise Benefits:

Uses 802.1X with EAP (Extensible Authentication Protocol) to authenticate users via a directory service (e.g., Active Directory).

Eliminates shared passwords (PSK) for authentication.

Provides strong encryption and resistance to brute-force attacks.

Incorrect Options:

A. Enable MAC Security:

MAC filtering is not secure because MAC addresses can be spoofed.

B. Generate a PSK for Each User:

Pre-shared keys (PSK) are used in WPA-Personal, not in an enterprise setting.

Does not scale well in corporate environments.

C. Implement WPS:

Wi-Fi Protected Setup (WPS) is a vulnerable security method meant for home users.

Not suitable for enterprise authentication.