CompTIA Network+ (N10-009)Networking ConceptsEasy
A network engineer is troubleshooting intermittent connectivity issues on a client workstation. The workstation can access local resources but cannot reach the internet. Upon checking the IP configuration, the engineer notices the default gateway address is incorrect. Which layer of the OSI model is primarily impacted by an incorrect default gateway configuration?
- ANetwork Layer (Layer 3)
- BPhysical Layer (Layer 1)
- CTransport Layer (Layer 4)
- DData Link Layer (Layer 2)
Show answer & explanationAnswer & explanation
Correct answer: A. Network Layer (Layer 3)
The default gateway is essential for routing traffic outside the local network. Routing decisions, which involve forwarding packets between different networks, are a primary function of the Network Layer (Layer 3) of the OSI model. An incorrect default gateway prevents the workstation from finding the correct path to remote destinations like the internet.
Why the other options are wrong
- B. The Physical Layer deals with physical transmission and media, not logical addressing or routing.
- C. The Transport Layer deals with end-to-end communication and port numbers, not the path packets take between networks.
- D. The Data Link Layer handles local frame delivery within a segment, using MAC addresses, not inter-network routing.
OSI Network Layer (Layer 3)
The third layer of the OSI model, responsible for logical addressing, routing packets between different networks, and determining the best path for data.
- Uses IP addresses for logical addressing.
- Routers operate at this layer.
- Responsible for fragmentation and reassembly of packets.
Memory trick: Please Do Not Touch Steve's Pet Alligator. (Physical, Data Link, Network, Transport, Session, Presentation, Application)