Paper Info
Title
On the Delays in Time-Varying Networks: Does Larger Service-Rate Variance Imply Larger Delays?
Abstract
In all networks, link or route capacities fluctuate for multiple reasons, e.g., fading and multi-path effects on wireless channels, interference and contending users on a shared medium, varying loads in WAN routers, impedance changes on power-line channels. These fluctuations severely impact packet delays. In this paper, we study delays in time-varying networks. Intuitively, we expect that for a given average service rate, an increased service rate variability yields larger delays. We find that this is not always the case. Using a queuing model that includes time-varying service rates, we show that for certain arrival rates, a queue with larger service rate variance offers smaller average delays than a queue with the same average service rate and lower service rate variance. We also verify these findings on a wireless testbed. We then study the conditions under which using simultaneously two independent paths helps in terms of delays, for example, in hybrid networks where the two paths use different physical layer technologies. We show that using two paths is not always better, in particular for low arrival rates. We also show that the optimal traffic splitting between the two paths depends on the arrival rate.
Year
DOI
Venue
2018
10.1145/3209582.3209603
Mobihoc '18: The Eighteenth ACM International Symposium on Mobile Ad Hoc Networking and Computing Los Angeles CA USA June, 2018
Keywords
Field
DocType
Delay analysis, Queueing, Time-varying networks
Shared medium,Wireless,Fading,Computer science,Network packet,Queue,Communication channel,Computer network,Queueing theory,Physical layer
Conference
ISBN
Citations 
PageRank 
978-1-4503-5770-8
0
0.34
References 
Authors
12
3
Name
Order
Citations
PageRank
Sébastien Henri131.53
Seva Shneer2135.60
Patrick Thiran32712217.24