TCP Stretch Acknowledgements and Timestamps: Findings and Implications for Passive RTT Measurement

This paper examines several TCP characteristics and their effect on existing passive RTT measurement techniques. In particular, using packet traces from three geographically distributed vantage points, we find relatively low use of TCP timestamps and significant presence of stretch acknowledgements. While the former simply affects the applicability of some measurement techniques, the latter may in principle affect the accuracy of RTT estimation. Using these insights, we quantify implications of common methodologies for passive RTT measurement. In particular, we show that, unlike delayed TCP acknowledgement, stretch acknowledgments do not distort RTT estimations.

[1]  Mischa Schwartz,et al.  ACM SIGCOMM computer communication review , 2001, CCRV.

[2]  Hao Jiang,et al.  Passive estimation of TCP round-trip times , 2002, CCRV.

[3]  Randy H. Katz,et al.  The effects of asymmetry on TCP performance , 1997, MobiCom '97.

[4]  Du Jinsong,et al.  Improving TCP performance over asymmetric networks , 2000, CCRV.

[5]  Kang Li,et al.  New Methods for Passive Estimation of TCP Round-Trip Times , 2005, PAM.

[6]  Kevin Jeffay,et al.  Variability in TCP round-trip times , 2003, IMC '03.

[7]  Vern Paxson,et al.  Measurements and analysis of end-to-end Internet dynamics , 1997 .

[8]  Feng Qian,et al.  An in-depth study of LTE: effect of network protocol and application behavior on performance , 2013, SIGCOMM.

[9]  Randy H. Katz,et al.  The effects of asymmetry on TCP performance , 1999, Mob. Networks Appl..

[10]  Stephen D. Strowes.  Passively measuring TCP round-trip times , 2013, Commun. ACM.

[11]  Godred Fairhurst,et al.  Performance issues in asymmetric TCP service provision using broadband satellite , 2001 .

[12]  Vern Paxson,et al.  TCP Congestion Control , 1999, RFC.

[13]  Stephen D. Strowes.  Passively measuring TCP round-trip times , 2013, Commun. ACM.

[14]  Mark Allman,et al.  A web server's view of the transport layer , 2000, CCRV.

[15]  J Gettys,et al.  Bufferbloat: Dark Buffers in the Internet , 2011, IEEE Internet Computing.

[16]  Donald F. Towsley,et al.  Inferring TCP connection characteristics through passive measurements , 2004, IEEE INFOCOM 2004.

[17]  Brian E. Carpenter,et al.  Some observations on individual TCP flows behavior in network traffic traces , 2011, 2011 11th International Symposium on Communications & Information Technologies (ISCIT).

[18]  Sally Floyd,et al.  Adding Acknowledgement Congestion Control to TCP , 2010, RFC.

[19]  Sally Floyd,et al.  Measuring the evolution of transport protocols in the internet , 2005, CCRV.

[20]  Brian Trammell,et al.  On the State of ECN and TCP Options on the Internet , 2013, PAM.