How TCP Works - No Operation Option

In this video we will take a look at the No Operation option in the TCP Handshake. This field acts as a filler to pad out the header size to a multiple of 4 bytes. Let's see why that is important.

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[JDBoelter]

Short and sweet, packing a lot of useful info about a single concept in a quick video. Exactly what I was hoping for. Great stuff.

[roadrush]

So sweet explanation, have started learning through your videos.

[slaye]

Are you going to cover selective acknowledgement that would be awesome!

[krishankrish]

I have a doubts for wireshark. could you clarify for me
i need to capture data from my mobile to whatever i am requested to other device for the example mobile to router

[balidu]

Maybe an idiot question but... why is the announced MSS 1460 while the TCP header size is 32 bytes ? (1500 - 20 - 32 = 1448)

[gamernick]

Hello, this has nothing to do with this video in particular but I am quite new to wireshark and I am having a problem. I noticed you are an expert, so I would appreciate your help. I cannot create config profiles and every time I launch the wireshark program on my mac it gives me an error that it cannot find profiles directory. The default profile just DNE in my computer. I tried a lot of different things from YouTube and Wireshark questions page, and I can't find anything on the topic. I can explain more if you need.

[杨森-ex]

I have a problem, I caputre a tcp stream, which like below. It's has more than 4 consecutive NOP. And I do not know why, can you help me? Thanks


Options: (24 bytes), Maximum segment size, No-Operation (NOP), Window scale, No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No-Operation (NOP), No
TCP Option - Maximum segment size: 1412 bytes
Kind: Maximum Segment Size (2)
Length: 4
MSS Value: 1412
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - Window scale: 5 (multiply by 32)
Kind: Window Scale (3)
Length: 3
Shift count: 5
[Multiplier: 32]
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - No-Operation (NOP)
Kind: No-Operation (1)
TCP Option - SACK permitted
Kind: SACK Permitted (4)
Length: 2
TCP Option - End of Option List (EOL)
Kind: End of Option List (0)
[SEQ/ACK analysis]
[Timestamps]