Wireshark · Wireshark-users: [Wireshark-users] Calculated Window Size

[Stuart Kendrick <skendric@xxxxxxxxx>]

How does this field work?

[...]
Window size value:  5792
[Calculated window size:  5792]
[...]
Window scale:  7 (multiply by 128)
    Kind:  Window Scale (3)
    Length:  3
    Shift count: 7
    [Multiplier: 128]
[...]
0030    16 a0 ....
0040    1e 34 a8 76 1f 26 01 03    03 07

In the hex decode, I see 0x16a0 at offset 0x0030, which converts neatly to TCP Window Size 5792 (in decimal).  Fine.  In the hex decode, I see '03 03 07' at the end of the TCP Frame ... which translates into Window Scale 3, Length 3, Shift Count 7.  Fine.

But I would expect Calculated window size to read 741,376 (i.e. 128 * 5792).  i.e. I think actual TCP Window Size is ~740K ... not ~6K.

Wireshark 1.7.1 (SVN Rev 41970)

What am I misunderstanding?

--sk

Stuart Kendrick
FHCRC