Tcptrace Time Sequence Graph
This graph format plots the "activity" on the connection. More
and more details is available as you "zoom in" with xplot. The Y
axis shows the sequence number space of the connection, the X axis
gives the time that those segments were active (sent/acked).
First graph
At this distance, you can make out the following features
- General Slope
- The slope of the curve shows the throughput over time.
- Red Letter R
- These are places where a retransmission took place. That
makes it easier to see where to zoom in.
Closeup 1
This is a closeup of the middle of the connection. At this
distance, you can make out the following features
- White Arrows
- The white arrows are segments sent. The upper and lower
limit of the arrows gives the sequence number of the first
and last byte in the segment.
- Red Arrows
- The red arrows are ALSO segments, but they're
retransmissions.
- Yellow Line
- The Yellow Line is the receive window advertised by the
receiver.
- Green Line
- The Green Line tracks the ACKs returned by the receiver.
- "Little Green Ticks"
- The little green tick marks below the green line on the
right side of the graph indicate duplicate ACKs (acking the
same sequence number again).
- "Little Yellow Ticks"
- The little yellow tick marks above the yellow line on the
right side of the graph indicate a receive window
advertisement that is the same as the previous advertisement.
Closeup 2
This is a closeup of the beginning of the connection. From this
distance, you can make out the following features
- SYN
- This is the syn segment being sent
SACKs
This closeup shows some selective ACKs (SACKS)
- Purple arrow
- This is a selective ACK
PUSHs
This closeup shows some segments sent with the PUSH bit set.
- Diamond-topped segment
- This is a PUSHed segment. This
feature was added after the graphs above, but segments whose upper
symbol is a diamond rather than an arrow were sent with the
PUSH bit set.
Shawn Ostermann
Last modified: Tue Jul 15 15:22:25 1997