For the success of critical applications in the IoT, there is a need to counteract the effects of external interference, especially when the unlicensed spectrum is used. One way of improving the performance is with a routing protocol that quickly reacts to changes in the environment and avoids path and/or frequencies with higher interference. In this paper, we propose an optimization to the RPL protocol, called TAMU‐RPL, that can keep a more accurate estimation of link quality to the neighbors and quickly react to degradation on the links. TAMU‐RPL also uses the quality of links at different frequencies and opportunistically avoids the ones with bad quality. It is evaluated through simulations with connectivity traces from a 40‐node test bed and in a real 5‐node deployment. We compare TAMU‐RPL with a baseline RPL protocol and a Dijkstra‐based shortest‐path algorithm. Results show that TAMU‐RPL can successfully explore the neighbors and obtain ETX values much closer to the ones obtained with a shortest‐path tree, even when link quality changes over time. In the simulation evaluation, TAMU‐RPL was able to double the number of packets received at the sink compared to RPL and reduced the average delay of packets (in time slots) by more than 10%. In the real deployment, the number of packets received at the sink was increased by more than 33%.
On Reducing Measurement Load on Control-Plane in Locating High Packet-Delay Variance Links for OpenFlow Networks
We previously proposed a method to locate high packetdelay
variance links for OpenFlow networks by probing multicast measurement
packets along a designed route and by collecting flow-stats of
the probe packets from selected OpenFlow switches (OFSs). It is worth AQ1
noting that the packet-delay variance of a link is estimated based on
arrival time intervals of probe packets without measuring delay times
over the link. However, the previously used route scheme based on the
shortest path tree may generate a probing route with many branches in a
large network, resulting in many accesses to OFSs to locate all high delay
variance links. In this paper, therefore, we apply an Eulerian cycle-based
scheme which we previously developed, to control the number of branches
in a multicast probing route. Our proposal can reduce the load on the
control-plane (i.e., the number of accesses to OFSs) while maintaining
an acceptable measurement accuracy with a light load on the data-plane.
Additionally, the impacts of packet losses and correlated delays over links
on those different types of loads are investigated. By comparing our proposal
with the shortest path tree-based and the unicursal route schemes
through numerical simulations, we evaluate the advantage of our proposal.
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- Award ID(s):
- 1818884
- NSF-PAR ID:
- 10289924
- Date Published:
- Journal Name:
- Lecture Notes on Data Engineering and Communications Technologies (LNDECT), Springer
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
