TCP Segment Header

We'll now study TCP headers. They're far more complex than UDP headers and really are what allow for TCP to work properly!


TCP headers play a crucial role in the implementation of the protocol. In fact, TCP segments without actual data and with headers are completely valid. They’re actually used quite often!

The size of the headers range from 20 - 60 bytes. Let’s discuss the header field by field.

Source and Destination Ports

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