TCP revisited: a fresh look at TCP in the wild

Since the last in-depth studies of measured TCP traffic some 68 years ago, the Internet has experienced significant changes, including the rapid deployment of backbone links with 1-2 orders of magnitude more capacity, the emergence of bandwidth-intensive streaming applications, and the massive penetration of new TCP variants. These and other changes beg the question whether the characteristics of measured TCP traffic in today’s Internet reflect these changes or have largely remained the same. To answer this question, we collected and analyzed packet traces from a number of Internet backbone and access links, focused on the “heavy-hitter” flows responsible for the majority of traffic. Next we analyzed their within-flow packet dynamics, and observed the following features: (1) in one of our datasets, up to 15.8% of flows have an initial congestion window (ICW) size larger than the upper bound specified by RFC 3390. (2) Among flows that encounter retransmission rates of m...

• Type: Conference
• Year: 2009
• Where: IMC
• Authors: Feng Qian, Alexandre Gerber, Zhuoqing Morley Mao, Subhabrata Sen, Oliver Spatscheck, Walter Willinger
• Keywords: IMC 2009, Internet Technology, Irregular Retransmissions, TCP Traffic, flow Clocking