📝 Nodes and Links in Data Link Layer

Q1. At which layer of the OSI model does a node communicate with the next node through a logical connection?

💡 Difficulty: easy | ✅ Correct: B

Q2. Suppose the link between R2 and R4 fails and traffic is rerouted through R3. What immediate effect does this have on the number of data‑link logical connections a packet experiences?

💡 Difficulty: medium | ✅ Correct: A

Q3. Assume each data‑link logical connection adds a processing delay \( d_p = 0.5 \) ms and a transmission delay \( d_t = 2 \) ms per hop. If a packet traverses four hops, what total delay is contributed solely by the data‑link layer?

💡 Difficulty: hard | ✅ Correct: D