What is the window size that is advertised by the Telnet client and the Telnet server? How does the value of the window size field vary as the connection progresses?

Question

What will be an ideal response?

Answer 1

The window size advertised by the TCP client is 5840 bytes and 5792 for telnet server. The window size does not change during the connection.
Frame 1
```
(74 bytes on wire, 74 bytes captured)
Arrival Time: Aug 23, 2003 04:26:58.297703000
Time delta from previous packet: 0.000000000 seconds
Time since reference or first frame: 0.000000000 seconds
Frame Number: 1
Packet Length: 74 bytes
Capture Length: 74 bytes
Ethernet II, Src: 00:06:5b:4b:e0:dd, Dst: 00:06:5b:4b:e1:da
Destination: 00:06:5b:4b:e1:da (DellComp_4b:e1:da)
Source: 00:06:5b:4b:e0:dd (DellComp_4b:e0:dd)
Type: IP (0x0800)
Internet Protocol, Src Addr: 10.0.5.11 (10.0.5.11), Dst Addr: 10.0.5.22 (10.0.5.22)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x10 (DSCP 0x04: Unknown DSCP; ECN: 0x00)
0001 00.. = Differentiated Services Codepoint: Unknown (0x04)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 60
Identification: 0xf5f2 (62962)
Flags: 0x04
.1.. = Don't fragment: Set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 64
Protocol: TCP (0x06)
Header checksum: 0x2699 (correct)
Source: 10.0.5.11 (10.0.5.11)
Destination: 10.0.5.22 (10.0.5.22)
Transmission Control Protocol, Src Port: 3115 (3115), Dst Port: telnet (23), Seq:

1157587888, Ack: 0, Len: 0

Source port: 3115 (3115)
Destination port: telnet (23)
Sequence number: 1157587888
Header length: 40 bytes
Flags: 0x0002 (SYN)
0... .... = Congestion Window Reduced (CWR): Not set
.0.. .... = ECN-Echo: Not set
..0. .... = Urgent: Not set
...0 .... = Acknowledgment: Not set
.... 0... = Push: Not set
.... .0.. = Reset: Not set
.... ..1. = Syn: Set
.... ...0 = Fin: Not set
Window size: 5840
Checksum: 0xc7ca (correct)
Options: (20 bytes)
Maximum segment size: 1460 bytes
SACK permitted
Time stamp: tsval 1611330, tsecr 0
NOP
Window scale: 0 (multiply by 1)
```
Frame 2
```
(74 bytes on wire, 74 bytes captured)
Arrival Time: Aug 23, 2003 04:26:58.297993000
Time delta from previous packet: 0.000290000 seconds
Time since reference or first frame: 0.000290000 seconds
Frame Number: 2
Packet Length: 74 bytes
Capture Length: 74 bytes
Ethernet II, Src: 00:06:5b:4b:e1:da, Dst: 00:06:5b:4b:e0:dd
Destination: 00:06:5b:4b:e0:dd (DellComp_4b:e0:dd)
Source: 00:06:5b:4b:e1:da (DellComp_4b:e1:da)
Type: IP (0x0800)
Internet Protocol, Src Addr: 10.0.5.22 (10.0.5.22), Dst Addr: 10.0.5.11 (10.0.5.11)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 60
Identification: 0x0000 (0)
Flags: 0x04
.1.. = Don't fragment: Set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 64
Protocol: TCP (0x06)
Header checksum: 0x1c9c (correct)
Source: 10.0.5.22 (10.0.5.22)
Destination: 10.0.5.11 (10.0.5.11)
Transmission Control Protocol, Src Port: telnet (23), Dst Port: 3115 (3115), Seq:

1148869796, Ack: 1157587889, Len: 0

Source port: telnet (23)
Destination port: 3115 (3115)
Sequence number: 1148869796
Acknowledgement number: 1157587889
Header length: 40 bytes
Flags: 0x0012 (SYN, ACK)
0... .... = Congestion Window Reduced (CWR): Not set
.0.. .... = ECN-Echo: Not set
..0. .... = Urgent: Not set
...1 .... = Acknowledgment: Set
.... 0... = Push: Not set
.... .0.. = Reset: Not set
.... ..1. = Syn: Set
.... ...0 = Fin: Not set
Window size: 5792
Checksum: 0x9131 (correct)
Options: (20 bytes)
Maximum segment size: 1460 bytes
SACK permitted
Time stamp: tsval 1611137, tsecr 1611330
NOP
Window scale: 0 (multiply by 1)
```