TSN
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... DSACK)
[RFC2883] and Duplicate TSN notifications, respectively. Using this
information, a TCP ...
... RFC3517]. The following steps MUST be taken upon the receipt
of each DSACK or duplicate TSN notification:
...
...
(A) Check the corresponding sequence range or TSN to determine
whether the segment has been retransmitted.
...
... of data. We can make no conclusions based on this
particular DSACK/duplicate TSN notification.
...
...
all sequence numbers or TSNs that have been acknowledged as
duplicates.
...