A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol Presented by : Frédéric CHALLITA-Cedric CHAUVENET-Andreas BRUNSCHWEILER 10/01/2016

SUMMARY Introduction and project context G3 PLC LOADng routing protocol Theoretical comparison between metrics nSim G3 simulator Simulation results Conclusion and perspectives Pour hiérarchiser et donc mettre en forme rapidement les paragraphes, appuyez sur : [Alt] [Maj] [] (flèche droite) pour descendre le texte d'un niveau, [Alt] [Maj] [] (flèche gauche) pour remonter le texte d'un niveau. Pour changer le titre et la date sur toutes les diapos : onglet [Insertion], "En-tête et pied de page", modifiez les donnés dans le champ "Pied de page", cliquez sur le bouton [Appliquer partout]. A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

01 Introduction

Context of the project Evolution of the current electrical network into smart grids Integration of information and telecommunications theory The client becomes an actor not only a consumer Linky project : promotes smart metering by using an interesting technology  PLC or Power Line Communications A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Context of the project Narrowband for Smart Metering applications : CENELEC A : 33 till 90 kHz Physical layer : OFDM (Orthogonal frequency division Multiplexing ) Channel Access managed in MAC layer by CSMA/CA Our focus in the Linky project is on the CENELEC A band dedicated to these use cases. The physical layer is commanded by the OFDM. This technique permits the simultaneaous transmission of different symbols without interference. Given that many meters want to send messages, the mangement an organisation of the channel access is important. This job is affected to the MAC layer. A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

G3 PLC LOADng routing protocol 01 G3 PLC LOADng routing protocol

G3 PLC LOADng routing Multitude of possible routes, RREQ, RREP, Route Costs, Route choices. Route breakage  Route Repair mechanism is triggered, and this operation will generate a flooding in the network A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Importance of routing Hostile propagation channel : time variable, frequency selective and dependent on the electrical equipment  Impedance variation Unpredictability of the created links caused by the variation of the channel’s impulse response. Many possible routes, many criteria to take into account Routing metrics: quantitative assessment that provides a cost for evaluating the path between communicating nodes A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

01 Routing metrics To this purpose we need mathematical functions that will help us choose the optimal path. A routing metric is a quantative evalauation of the link based on criterion.

Routing metrics Composite contains many factors to take into account : LQI (adpKq=10)), modulation, number of hops (adpKh=4), number of active tones . 𝑅𝑜𝑢𝑡𝑒𝐶𝑜𝑠𝑡=10∗ 255−𝐿𝑄𝐼 255 +4 Capacity associates route costs to each couple (modulation/nb. of active tones) Alternative configuration of the default Composite by setting adpKr=20 (for ROBO mode). A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Evolution of Route Cost We can see a great dynamic range for route costs in the case of the Capacity metric and we can also see that this metric penalises the ROBO mode sensitive to impulsive noises… A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Aspects of the Composite metric If 0<LQI<255  4<RC<14 . LQI limit of ROBO mode=52  RC=12 LQI max observed = 140  RC=9 : perfect link Small range between ROBO and perfect link This fact can priviliege routes with ROBO links rather than routes with 2 hops D8PSK links because 2*9 > 12 If we had the whole range of LQI  2*4<12 ROBO modulation is sensitive to impulsive noise and random attenuations affecting the propagation channel These facts justify the promising use of Capacity metric It will associate a higher route cost for ROBO mode. A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Dynamic range of SNR for different modulations A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

01 nSim G3 Simulator

Presentation Dedicated to the simulation of the G3 specification User friendly graphical interface with simple configuration of the propagation channel Configuration of noise, attenuation, sub-carriers, etc. Possibility to change MAC, ADP, PHY parameters and test their influence Our goal : test the performances of the different routing metrics Validation Comparison with lab results Comparative study of routing metrics A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

01 Simulation results

Topology and results A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

Average RTT time A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

01 Conclusion

Conclusion and perspectives Enhanced performances measured with the capacity metric or alternative routing configuration of composite metric in different aspects Success rate without droprate Success rate with droprate Average throughput (≈50% better) Interdependence between the different layers leads to the optimization of the CSMA/CA ( extension of the contention window) Testing the new parameter set of the Composite metric in real field conditions A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol – 11/9/2016

A Comparative Study of Routing Metrics in G3-PLC LOADng routing protocol Presented by : Frédéric CHALLITA-Cedric CHAUVENET-Andreas BRUNSCHWEILER 10/01/2016