At which OSI layer are you primarily observing when monitoring traffic on a router for investigative purposes?

At which OSI layer are you primarily observing when monitoring traffic on a router for investigative purposes?

• A. Network
• B. Transport
• C. Data Link
• D. Session

Answer: (A)

Monitoring traffic on a router centers on the Network layer because a router’s primary role is to forward packets between networks using IP addresses. The IP header carries the source and destination addresses and dictates routing decisions, which are the essence of layer 3 activity. While you can encounter data from other layers inside packet payloads (like transport layer port numbers or frames on a local link), the key observable aspect when analyzing router traffic is IP-based routing and addressing. So, the most relevant layer you’re observing is the Network layer.

Monitoring traffic on a router centers on the Network layer because a router’s primary role is to forward packets between networks using IP addresses. The IP header carries the source and destination addresses and dictates routing decisions, which are the essence of layer 3 activity. While you can encounter data from other layers inside packet payloads (like transport layer port numbers or frames on a local link), the key observable aspect when analyzing router traffic is IP-based routing and addressing. So, the most relevant layer you’re observing is the Network layer.