Source-Level IP Packet Bursts: Causes and Effects

Authors: Hao Jiang, Constantinos Dovrolis

Complete Citation

Hao Jiang, Constantinos Dovrolis, Source-Level IP Packet Bursts: Causes and Effects, IMC'03, DOI Bookmark: http://doi.acm.org/10.1145/948205.948245

Abstract

By source-level IP packet burst, we mean several IP packets sent back-to-back from the source of a flow. We first identify several causes of source-level bursts, including TCP’s slow start, idle restart, window advancement after loss recovery, and segmentation of application messages into multiple UDP packets. We then show that the presence of packet bursts in individual flows can have a major impact on aggregate traffic. In particular, such bursts create scaling in a range of timescales which corresponds to the burst duration. Uniform “spreading” of bursts in the time axis reduces the scaling exponent in short timescales (up to 100-200ms) to almost zero, meaning that the aggregate traffic becomes practically uncorrelated in that range. This result provides a plausible explanation for the scaling behavior of Internet traffic in short timescales. We also show that removing packet bursts from individual flows reduces significantly the tail of the aggregate marginal distribution, and it improves queueing performance, especially in moderate utilizations (50-85%).

Annotations

This paper focused on the causes and effects of packet bursts from individual flows in IP networks.

Causes for source-level bursts:

• UDP message segmentation.
• Slow start.
• Loss recovery with Fast Retransmit.
• Unused congestion window increases.
• ACK compression.
• Cumulative or lost ACKs.
• Idle restart timer bug.
• Bursty applications.
• Packet (ACK) reordering.

Effect of burst:

• Energy plot and scaling behavior:
  

• Tail distribution of the amount of bytes in non-overlapping 10ms intervals:
  

• Queueing performance: