Networking - MCQ Practice Questions

A company deploys a VPN solution. At which OSI layer does the VPN primarily encrypt data before transmission?

During a network troubleshooting session, a technician finds that DNS resolution fails while DHCP assignment succeeds. Which layers are functioning and which is failing?

A firewall is configured to block traffic on specific ports. At which minimum OSI layer must the firewall operate to enforce this rule?

In a complex network architecture, data flows through multiple devices: modem → switch → router → firewall → server. Which device primarily operates at Layer 3?

A developer needs to ensure data compression before transmission over a network. Which OSI layer should handle this function?

Which of the following is NOT a function of the Physical Layer in the OSI model?

In a network troubleshooting scenario, a technician finds that devices cannot communicate despite having correct IP addresses. The issue is at the layer responsible for converting IP addresses to MAC addresses. Which OSI layer is involved?

An organization experiences issues with email delivery. The protocol SMTP operates at which OSI layer?

During a network analysis, it is observed that frames are being retransmitted at a specific layer due to collision detection. Which layer implements CSMA/CD (Carrier Sense Multiple Access/Collision Detection)?

Which of the following best describes the relationship between the OSI model and TCP/IP model?

Consider a scenario where a web server responds to a client request. Trace the data flow: which layer encapsulates the HTTP response into segments before transmission?

In the context of the OSI model, which layer is responsible for ensuring reliable, in-order delivery of data?

Which protocol operates at the Data Link Layer and is primarily used in Ethernet networks?

A network administrator needs to implement a solution that translates character encoding formats between different systems. Which OSI layer provides this functionality?

The TCP/IP model has 4 layers, while the OSI model has 7 layers. Which OSI layers are combined into the TCP/IP Application Layer?

Which protocol operates at the Transport Layer and is connectionless?

In the OSI model, what does the Presentation Layer primarily do?

A technician notices that devices can ping each other but cannot access web services. At which OSI layer might the problem exist?

Which OSI layer is responsible for managing access to the shared physical medium?

During network troubleshooting, a frame is found to have an incorrect FCS (Frame Check Sequence). At which layer would this be detected and corrected?