Fluid analysis of delay and packet discard performance for QoS support in wireless networks

Marwan M. Krunz, Jeong Geun Kim

Research output: Contribution to journalArticlepeer-review

76 Scopus citations


Providing quality-of-service (QoS) guarantees over wireless links requires through understanding and quantification of the interactions among the traffic source, the wireless channel, and the underlying link-layer error control mechanisms. In this paper, we account for such interactions in an analytical model that we use to investigate the delay distribution and the packet discard rate (PDR) over a wireless link. In contrast to previous studies, our analysis accommodates the inherent autocorrelations in both the traffic source as well as the channel error characteristics. An on-off fluid process is used to model the arrival of packets at the transmitter. These packets are temporarily stored in a first-in-first-out (FIFO) buffer before being transmitted over a channel with a time-varying and autocorrelated service rate. Using fluid analysis, we first derive the distribution for the queueing delay at the transmitter. As part of this analysis, we solve a fundamental fluid problem, namely, the probability distribution for the workload generated by a two-state fluid source over a fixed time interval. We then use the delay analysis to derive the PDR at the receiver (a packet is discarded when the maximum number of retransmissions is reached). A closed-form expression for the effective bandwidth subject to a delay constraint is provided as a function of the source, channel, and error scheme parameters. This expression enables fast assessment of the bandwidth requirement of real-time traffic over QoS-based wireless networks. Numerical results and simulations are used to verify the adequacy of the analysis and to study the interactions among various system parameters.

Original languageEnglish (US)
Pages (from-to)384-395
Number of pages12
JournalIEEE Journal on Selected Areas in Communications
Issue number2
StatePublished - Feb 2001


  • Delay distribution
  • Fluid analysis
  • Packet discard rate
  • QoS
  • Wireless networks

ASJC Scopus subject areas

  • Computer Networks and Communications
  • Electrical and Electronic Engineering


Dive into the research topics of 'Fluid analysis of delay and packet discard performance for QoS support in wireless networks'. Together they form a unique fingerprint.

Cite this