-specification. A single request consists of a number of packets that sent a
-to the \emph{echo-server} and back. The TCP specification state that such a
-transaction requires the following messages.
-
-\begin{center}
- Script $-$ SYN $A$ $\rightarrow$ SUT \\
- Script $\leftarrow$ SYN-ACK $(A+1)$ $B$ $-$ SUT \\
- Script $-$ ACK $(A+1)$ $(B+1)$ $\rightarrow$ SUT \\
- Script $-$ ACK-PUSH $(A+1)$ $(B+2)$ \emph{msg} $\rightarrow$ SUT \\
- Script $\leftarrow$ ACK $(A+2+msg_{length})$ $(B+3)$ $-$ SUT \\
- Script $\leftarrow$ ACK-PUSH $(A+2+msg_{length})$ $(B+3)$ \emph{msg} $-$ SUT
-\end{center}