State the main purpose of Spanning Tree Protocol (STP) in Ethernet networks. Explain how switching loops occur in a network. Briefly explain how STP prevents switching loops.

What is Dynamic ARP Inspection (DAI)? How does it detect and prevent ARP spoofing attacks? Explain how Dynamic ARP Inspection (DAI) uses the DHCP snooping binding database to prevent ARP spoofing attacks in a switched enterprise network.

How does Dynamic ARP Inspection (DAI) help prevent ARP spoofing with the aid of the DHCP snooping binding database?

Explain the main differences between IPv4 and IPv6 addressing. Include at least three key differences and state the IPv6 equivalent of ARP.

A computer can ping 8.8.8.8 but cannot access websites using domain names. Explain the likely cause and describe how you would diagnose and resolve the problem using standard network utilities.

Explain the role of Link-State Advertisements (LSAs) in OSPF and how the Dijkstra SPF algorithm uses the information contained in LSAs to build the routing table.

List the top five steps of the BGP path-selection decision process in priority order (highest priority first). Briefly describe how each criterion influences the selection of the best route when multiple routes to the same destination are available.

Using VLSM, subnet the block 10.100.0.0/22 to allocate address space for the following departments. Write the Subnet Address and CIDR mask for each: Dept A: 250 hosts, Dept B: 120 hosts, Dept C: 50 hosts. (Allocate efficiently and show the order of allocation.)

Divide the network 192.168.10.0/24 into four equal-sized subnets and determine the network address, subnet mask, usable host range, and broadcast address of each subnet.

Explain how Port Address Translation (PAT) works and why it is more commonly used than Static or Dynamic NAT in most enterprise and home networks.

What is network topology? Explain the different network topologies.

Draw and explain the seven layers of the OSI model.

Differentiate between a firewall, an Intrusion Detection System (IDS), and an Intrusion Prevention System (IPS), and explain how each contributes to network security.

Explain how a Man-in-the-Middle (MitM) attack can compromise a customer's online banking session and describe technologies to mitigate the threat.

Several computers in a bank branch become encrypted by ransomware. Describe the immediate actions the IT team should take in chronological order.

Consider Employees (EmpID, Name, Department, Salary). Write an SQL query to retrieve employees whose salaries are greater than the average salary of their respective departments.

Explain the meaning of chmod 750 backup.sh and chown root:admin backup.sh. Write a command to grant the owner read/write/execute permissions, the group read/execute permissions, and no permissions to others.