An Investigation into Transport Protocols and Data Transport ...

9.3. Internet Transfers 235
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Goodput (mbit/sec)
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Standard TCP HSTCP ScalableTCP HTCP FAST BicTCP
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Figure 9.30: Goodput from CERN to Dublin.
9.3.3 Results: CERN to Dublin
Goodput
Figure 9.30 shows the transfer results from CERN to Dublin. All algorithms,
including Standard TCP, are able to transfer at high rates due to the relatively
low latencies of the network path.
Unlike previous results with Stanford which show a few outliers above the
median goodput, the Dublin link shows that there are a few occasions where
the measured goodput of the New-TCP algorithms were lower. Whist the
number of these points are small, they suggest rare instances of competing
traffic on this network path which reduces the goodput performance.
Out of the protocols, BicTCP appear to have the highest goodput, with
also the smallest inter-quartile range. However, FAST maintains similar
median goodput values to that of BicTCP, but shows a larger inter-quartile
and normal range of values. ScalableTCP maintains a very narrow goodput
range, however, maintains a slightly lower goodput when compared to FAST
and BicTCP.
HSTCP, even with its gently aggressive deviation from standard AIMD
at low cwnd values, demonstrates higher goodput performance with larger