Network-Wide Measurements of TCP RTT in 3G

  • Authors:
  • Peter Romirer-Maierhofer;Fabio Ricciato;Alessandro D'Alconzo;Robert Franzan;Wolfgang Karner

  • Affiliations:
  • Forschungszentrum Telekommunikation Wien, Austria;Forschungszentrum Telekommunikation Wien, Austria and Università del Salento, Italy;Forschungszentrum Telekommunikation Wien, Austria;Forschungszentrum Telekommunikation Wien, Austria;mobilkom austria AG,

  • Venue:
  • TMA '09 Proceedings of the First International Workshop on Traffic Monitoring and Analysis
  • Year:
  • 2009

Quantified Score

Hi-index 0.00

Visualization

Abstract

In this study we present network-wide measurements of Round-Trip-Time (RTT) from an operational 3G network, separately for GPRS/EDGE and UMTS/HSxPA sections. The RTTs values are estimated from passive monitoring based on the timestamps of TCP handshaking packets. Compared to a previous study in 2004, the measured RTT values have decreased considerably. We show that the network-wide RTT percentiles in UMTS/HSxPA are very stable in time and largely independent from the network load. Additionally, we present separate RTT statistics for handsets and laptops, finding that they are very similar in UMTS/HSxPA. During the study we identified a problem with the RTT measurement methodology -- mostly affecting GPRS/EDGE data -- due to early retransmission of SYNACK packets by some popular servers.