A packet sniffer tool captures data at Layer 2. Which information would be visible in the captured frames?
AIP addresses and port numbers
BMAC addresses and frame structure
CApplication-level data and HTTP headers
DDNS queries and domain names
Correct Answer:
B. MAC addresses and frame structure
EXPLANATION
Layer 2 (Data Link Layer) operates with MAC addresses and frames. IP addresses (Layer 3) and application data (Layer 7) would not be directly visible at Layer 2 without further analysis.
A manufacturing facility's IoT devices communicate using raw bit transmission over twisted pair cables. Which OSI layer(s) are being utilized?
ALayers 1 and 2
BLayer 1 only
CLayers 2 and 3
DLayers 3, 4, and 5
Correct Answer:
A. Layers 1 and 2
EXPLANATION
Raw bit transmission over physical media (twisted pair cables) involves Layer 1 (Physical Layer). Data Link Layer (Layer 2) protocols handle the framing and transmission rules for these bits.
In a corporate network, certain applications require guaranteed delivery and error checking, while others prioritize speed. Which Layer 4 protocols would best serve these requirements respectively?
ATCP for speed; UDP for guaranteed delivery
BUDP for both; TCP for neither
CTCP for guaranteed delivery; UDP for speed
DBoth TCP and UDP provide identical services
Correct Answer:
C. TCP for guaranteed delivery; UDP for speed
EXPLANATION
TCP provides reliable, ordered delivery with error checking; UDP prioritizes speed with minimal overhead. Choice of protocol depends on application requirements.
A network administrator needs to implement a solution to prevent unauthorized access to sensitive data transmitted over the network. Which OSI layer would be most appropriate for implementing encryption?
ALayer 2 - Data Link Layer
BLayer 4 - Transport Layer
CLayer 6 - Presentation Layer
DLayer 7 - Application Layer
Correct Answer:
C. Layer 6 - Presentation Layer
EXPLANATION
The Presentation Layer (Layer 6) is responsible for data encryption, decryption, compression, and translation, making it the appropriate layer for implementing encryption services.
During a network audit, it is discovered that HTTP traffic is being intercepted and modified. At which minimum OSI layer would a device need to operate to perform this attack?
ALayer 3 - Network Layer
BLayer 4 - Transport Layer
CLayer 5 - Session Layer
DLayer 7 - Application Layer
Correct Answer:
D. Layer 7 - Application Layer
EXPLANATION
HTTP is an Application Layer (Layer 7) protocol. To intercept and modify HTTP traffic, an attacker must operate at Layer 7 where the actual content is accessible.
A company experiences intermittent network connectivity issues. When troubleshooting, an administrator discovers that the issue occurs only when data passes through a specific gateway. At which OSI layer(s) should the administrator focus their investigation?
ALayers 1 and 2 only
BLayers 3 and 4 primarily, with possible involvement of Layer 7
CLayer 2 only
DLayer 1 only
Correct Answer:
B. Layers 3 and 4 primarily, with possible involvement of Layer 7
EXPLANATION
A gateway typically operates at Layer 3 (routing) and Layer 4 (protocol conversion), and may involve Layer 7 for application-level filtering. Issues at the gateway level suggest Layer 3-4 problems.
