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The increasing popularity of video streaming and conferencing services have altered the nature of Internet traffic. In this paper, we take a first step toward quantifying the impact of this changing nature of traffic on the Quality of Experience (QoE) of popular video streaming and conferencing applications. We first analyze the traffic characteristics of these applications and of backbone links, and show how simple multipath routing may adversely impact application QoE. To mitigate this problem, we propose a new routing path selection approach, inspired by the TCP timeout computation algorithm, that uses both the average and variation of path load. Preliminary results show that this approach improves application QoE by on average 14% and packet latency by 11% for video streaming and conferencing applications, respectively.
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A Formal Analysis of Karn’s Algorithm
The stability of the Internet relies on timeouts. The timeout value, known as the Retransmission TimeOut (RTO), is constantly updated, based on sampling the Round Trip Time (RTT) of each packet as measured by its sender -- that is, the time between when the sender transmits a packet and receives a corresponding acknowledgement. Many of the Internet protocols compute those samples via the same sampling mechanism, known as Karn's Algorithm. We present a formal description of the algorithm, and study its properties. We prove the computed samples reflect the RTT of some packets, but it is not always possible to determine which. We then study some of the properties of RTO computations as described in the commonly used RFC6298. All properties are mechanically verified.
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- Award ID(s):
- 1918429
- PAR ID:
- 10462015
- Editor(s):
- David Mohaisen, Thomas Wies
- Date Published:
- Journal Name:
- Lecture notes in computer science
- Volume:
- LNCS
- Issue:
- 14067
- ISSN:
- 0302-9743
- Page Range / eLocation ID:
- 43-61
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
