Does each ACK packet also include window size in TCP connection?

Question

While solving a question I ran through the following statement:

 RcvWindow is the part of the receiver's buffer that's changing all the time depending on the processing capability at the receiver's side and the network traffic

So for the above to happen, sender must know about the same. So does window size is also conveyed with ACK? If not then how does sender knows about the changed window size?

Comments

Just saw TCP header format in which there is a field for window size along with acknowledgement number. I believe this field conveys to the sender.

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Sender doesnot need to know about it

Because Sender just sends, what it gets to receiver. Receiver buffer changes according to how much data it can accomodate.

That is why there are 3 strategy to sending data

like stop and wait GBN and selective repeat

Sequence number actually concern with it

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Use of window field in TCP header:

The number of data octets beginning with the one indicated in the acknowledgment field which the sender of this segment is willing to accept.

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This might be of help : https://www.cse.iitk.ac.in/users/dheeraj/cs425/lec15.html

• Window Size : Flow control in TCP is handled using a variable-size sliding window. The Window Size field tells how many bytes may be sent starting at the byte acknowledged. Sender can send the bytes with sequence number between (ACK#) to (ACK# + window size - 1) A window size of zero is legal and says that the bytes up to and including ACK# -1 have been received, but the receiver would like no more data for the moment. Permission to send can be granted later by sending a segment with the same ACK number and a nonzero Window Size field.

This seems to suggest that receiver window size also determines the size of data that can be sent over the connection.

@shrestha, since we have a concept of Advertised window at the receiver side, i think it implies that receiver is informing the sender about the max size it can accept at that particular time.