Sliding window protocol when number of packets is equivalent to the window size I am currently taking a course in computer networking and I am curious about the following situation:

Given $n$ packets and a window size of $n$ (i.e., the number of packets is equivalent to the window size), what would happen in the following scenario?:

Packet 1 is sent by Host A and the corresponding ACK is received. Do the window boundaries need to be updated to $[2:n + 1]$ or would it remain as $[1:n]$ (as there would be $n - 1$ remaining packets (strictly less than the window size, $n$)?
Definitely, the window boundaries will be updated, in other words, the window will be shifted regardless of the fact remaining packets are strictly less than window size.

But the main point is after shifting,window will not be fully      occupied.The window in sliding window protocol is a buffer, which stores only those packets whose acknowledgement is not received. But because the packet 1's ack is received, it would no longer remain in the window.