Problem Statement
Explain how the Sliding Window Protocol improves efficiency over Stop-and-Wait.
Explanation
The Sliding Window Protocol allows multiple frames to be sent before needing an acknowledgment, increasing channel utilization. The sender maintains a window of unacknowledged frames, and the receiver acknowledges as frames arrive, sliding the window forward. This reduces idle time and maximizes throughput, especially in long-delay networks. Variants include Go-Back-N and Selective Repeat ARQ.