Sequence Number Seq

Transport 4 octets TCP segment unverified

Position of the first data octet in this segment within the stream.

Reading a capture

Not related to the Sequence Number in the 802.11 header several lanes above. That one counts frames on the air; this one counts bytes in a stream, and they have nothing to do with each other.

Where it sits

TCP Segment > Sequence Number

Open in the explorer — TCP over IPv4, in a protected QoS Data frame, aggregated
Open in the explorer — TCP over IPv4, in a protected QoS Data frame
Open in the explorer — TCP over IPv4, in an open QoS Data frame

Accuracy

Clause: RFC 9293 §3.1
Byte order: big-endian — network byte order
Verified: Not verified against the standard. Treat this as a claim, not a fact.