Currently, there are two open position:

PhD position(1): Designing Fault-Tolerant Distributed Systems for Nanosat Constellations
PhD position(2): Fluid Modelling of Distributed System in Swarms of Cyber-Physical Systems (applications on nanosats/drones/autonomous underwater vehicles)
PhD position(3): Designing Distributed System for Mobile Computing (applications on IoT/drones)


PhD position: Designing Fault-Tolerant Distributed Systems for Nanosat Constellations

Keywords: orbital edge computing, replication, distributed and resilient computing, fault tolerance, intermittent computing, nanosats' subsystems.

Context

The recent deployment of an increasing number of nanosatellites in low-earth orbit (LEO) presents new opportunities for space applications [DKL + 17, DL20]. Built atop small-sized yet powerful blocks,a.k.a. CubeSats or simply nanosats, nanosatellite constellations emerge as promising platforms for massive sensing and large-scale distributed computing. Indeed, they represent a cheaper, competitive alternative for traditional satellite systems for a wide range of application domains such as earth observation and defence.
However, the design of distributed, intelligent systems based on nanosats is particularly challenging: nanosats have more stringent physical limitations with respect to processing/networking capability, energy supply, and connectivity among nanosats. Moreover, the use of cheaper components and subsystems might expose the emerging nanosat applications to performance degradation or complex failures. Therefore, novel resilient distributed applications and protocols should be designed and evaluated to make efficient and reliable use of the resources of nanosats at the orbital edge. The proposed doctoral project aims to enable a first-of-its-kind orbital edge computing subsystems with nanosats and to design novel techniques to support reliable and efficient data processing for emerging sensing application like earth observation with the proposed orbital edge computing platform. In order to achieve this challenging goal, we will conduct interdisciplinary, collaborative research to answer the following questions:

  • How to enable distributed computing on a nanosat?
    We will survey the design and implementation of state-of-the-art building blocks including suitable communication protocols and specific subsystems interfaces and abstractions for computing on nanosats.
  • How to build a resilient computing system with a set of nanosats?
    We will investigate distributed systems problems and propose specific solutions for dynamic reconfiguration mechanisms, consensus algorithms, and data replication schemes on nanosats systems. For that, we will take into account the ongoing research on related topics at CNES, including clock synchronization.

Proposed research

This doctoral research project aims to address the above scientific challenges as follows:

  • Leveraging non-expensive, failure-prone nanosats' components. We will explore the design space and the performance evaluation of distributed system on nanosats constellations. Based on an existing, representative hardware platform proposed by the CNES, we aim to conduct a systematic study on how different choices of distributed systems primitives and designs affect the performance of key services, such as special-purpose sensing and distributed processing application. To this end, we will execute specific benchmarks to identify design opportunities, to assess the impact of different failures and to better understand the eventual trade-offs for distributed computing on nanosats.
  • Resilient edge computing with constellations of nanosats. An interesting solution for processing large amount of sensing data is to build a distributed computing system with a set of nanosats. So that we will re-examine many assumptions in traditional distributed systems in the presence of processing and interconnectivity limitations of nanosats. In particular, we aim to design novel resilient applications and protocols for fault-tolerant distributed services, e.g., dynamic reconfiguration mechanisms, consensus protocols, and replication schemes. Based on these fundamental services, we will enable intelligent, distributed computing on nanosats constellations.


Currently, the availability and resilience of traditional, cloud-based distributed system are commonly guaranteed by a replication protocol based on replicated state machine (RSM). Such a protocol implements a consensus algorithm to enable strong consistency, like Fast Paxos [Lam06] and Raft [OO14]. Strongly consistent replication is key to efficient implementation of critical distributed systems’ building blocks, like distributed lock manager, reliable configuration or transactional key-value store. To our knowledge though, such protocols have never been designed and extensively evaluated on nanosatellite constellations.

Requirements and application

In this research project, we intend to explore both a fundamental and an applied aspects. Candidates to this position should hold a Master’s degree in Computer Science/Informatics, Mathematics, Physics or a related field by the starting date of the doctoral project. They must be excited by research in distributed systems/computing, distributed algorithms, orbital edge computing, and/or intermittent computing, and should have an excellent academic record in one of these areas. Familiarity with machine learning and graph theory/algorithms would be appreciated but they are not essential. Teamwork and communication skills are key to this position, and industrial experience is a plus.
Knowledge of French is not required.
To apply, please send the following information to silvestre@enac.fr(Subject=PhD position [ENAC-TESA-PhD24]: fault-tolerant distributed algorithms):

  • Curriculum Vitæ
  • Letter of motivation that should describe the applicant's background in the areas of the project, reason for interest in the project, and future plans
  • A list of courses and grades of the last three years of study (an informal transcript is OK).
  • Names and contact details of at least two people who can write you references, whom we will contact directly.
  • If relevant, a link to your publications and/or open-source developments.

Application deadline: 31 October 2023.
This fully-funded PhD starts in April 2024 and the duration of the contract/scholarship is 3 years.

Eligibility criteria and Benefits

Applicants of any nationality can apply, but applicants must not have a doctoral degree already or been enrolled in a PhD/doctoral program.
Benefits include:

  • French government strongly subsidizes higher education, therefore the tuition fees are among the more competitive in Europe
  • Social security coverage included
  • Subsidized meals
  • Partial reimbursement of public transport costs
  • Social, cultural and sports events and activities

About ENAC

The ENAC, National School of Civil Aviation, is located in Toulouse, France, the centre of the European aerospace industry (e.g., AirBus, Thales, and CNES). It offers an ideal working environment, where researchers can focus on developing new ideas, collaborations and projects.
Our research topics at ENAC Lab include emerging CPS design (e.g., drones and nanosatellites), aviation safety and security, sustainable transportation development, and aeronautical computer-human interactions. For further information, please consult our site.
The proposed research will be developed in the ENAC research laboratory, ENAC Lab, in close cooperation with TéSA, an important industrial partner in Toulouse and the University of Adelaide in Australia.

References

[DKL + 17] K. Devaraj et al. Dove high speed downlink system. 2017.
[DL20] B. Denby and B. Lucia. Orbital edge computing: Nanosatellite constellations as a new class of computer system. In the ASPLOS, 2020.
[Lam06] L. Lamport. Fast paxos. Distributed Computing, 2006.
[OO14] D. Ongaro and . Ousterhout. In search of an understandable consensus algorithm. In the ATC, 2014.




PhD position: Fluid Modelling of Distributed System in Swarms of Cyber-Physical Systems (applications on nanosats/drones/autonomous underwater vehicles)

Keywords: Distributed algorithms; queueing network model; parallel computing; computational fluid dynamics; edge computing; dynamic, mobile networks; differential equations; simulation

Context

Swarm of Cyber-Physical Systems (CPS)[1] offer novel opportunities in many emerging application domains, such automated surveillance systems with swarm of drones, dynamic earth observation with (nano-)satellite constellations, deep underwater exploration with swarms of unmanned vehicle[2]. However, CPS swarms introduce multiple non-trivial challenges for both system designers and operators, particularly in terms of complexity and cost of the development life-cycle. In this context, this project aims at providing a novel fluid-model-based methodology to assist system designers and operators in building and evaluating the performance of new distributed system in CPS swarms. To foster the initial research efforts in fluid modelling and simulation, the target methodology will leverage and extend the software library and framework recently developed by B. Chianca in his doctoral project[3].
Our approach relies on a macroscopic modelling (or fluid) of the dynamics of messages exchanged in a network of mobile nodes, computed as the limit over a large number of exchanged messages per unit of time. This approach, which is based on an asymptotic analysis of network messages dynamics, was successfully extended from the doctoral project of A. De Cecco[4], who proposed a fluid modelling of avionics AFDX networks. Such techniques provide simplified yet relevant design of distributed mobile systems that permit greatly reducing the simulation run-time when compared to state-of-the-art simulators[3]. We argue that fluid modelling of distributed system in CPS swarms affords system designers and operators valuable opportunities to promptly verify properties and to estimate the performance of distributed services in mobile, dynamic environments[5].

Proposed research

In this project, we intend to extend our current methodology in order to enable more accurate and flexible distributed systems simulations and performance evaluation reporting in the face of continuously evolving network topologies. For instance, we are particularly interested in accurately reproducing the dynamic performance variations of mobile, distributed inter-processes communications without compromising the overall simulation run-time. The primary goal of research on improving this modelling methodology is to assist not only the design of novel, fault-tolerant distributed systems but also to contribute to enhance resource allocation and mobility within a CPS swarm. Therefore, this study will consider the entire life-cycle of distributed services on CPS swarms, including the development, planning and operations[6]. Consequently, we will pursue the following specific goals in this project:

  • Contribute to verify properties of distributed systems w.r.t. mission level planning of motion and navigation of CPS swarms;
  • Contribute to the macroscopic modelling of the network dynamics due to unwanted swarm events such as system reconfigurations or different, challenging failures models (including byzantine failures);
  • Promptly estimate the performance of distributed systems in CPS swarm in an efficient manner, contributing therefore to the design, planning and operations of emerging services for CPS swarms;
  • Develop and release a stable, open source software library and framework for accurate, lightweight simulations of emerging distributed systems atop of CPS swarms.



To reach these goals, we intend to explore both fundamental and applied aspects. To improve our current queueing network model, multiple equations and key parameters should be thoroughly reviewed and tuned properly. Moreover, we aim to validate our modelling methodology by comparing its results with real experiments. To this end, we expect to run experiments with fleets of unmanned aerial vehicles (UAVs), commonly known as drones, in the UAV experimental flight facility of our campus. In addition, we aim to survey and evaluate through extensive simulations a wide variate of CPS swarms, such as swarms of unmanned underwater vehicles or constellations of (nano-)satellites, in close cooperation with our French and foreign partners.

Requirements and application

Candidates to this position should hold a Master's degree in Computer Science/Informatics, Mathematics, Physics or a related field by the starting date of the PhD. They must be excited by research in distributed systems, distributed algorithms, computational fluid dynamics, and/or programming languages, and should have an excellent academic record in one of these areas. Familiarity with queueing network model and differential equations would be appreciated. Teamwork and communication skills are key to this position, and industrial experience is a plus.
Knowledge of French is not required.
To apply, please send the following information to ds-resco-recruitment@lists.recherche.enac.fr(Subject=PhD position [ENAC-ONERA-PhD23]: Fluid Modelling of Distributed System in CPS Swarms):

  • Curriculum Vitæ
  • Letter of motivation that should describe the applicant's background in the areas of the project, reasons for interest in the project, and future plans
  • A list of courses and grades of the last two years of study (an informal transcript is enough).
  • Names and contact details of at least two people who can write you references, whom we will contact directly.
  • If relevant, a link to your publications and/or open-source developments.

Application deadline: 15 May 2023.
This fully-funded PhD starts on 1 October 2023 and the duration of the contract/scholarship is 3 years.

Eligibility criteria and Benefits

Applicants of any nationality can apply, but applicants must not have a doctoral degree already or been enrolled in a PhD/doctoral program.
Benefits include:

  • French government strongly subsidizes higher education, therefore the tuition fees are among the more competitive in Europe
  • Social security coverage included
  • Subsidized meals
  • Partial reimbursement of public transport costs
  • Social, cultural and sports events and activities

About Onera and ENAC research laboratories

Onera, the French Aerospace Lab, and ENAC, National School of Civil Aviation, are both located in Toulouse, France, the centre of the European aerospace industry. Our research laboratories offer ideal working environments, where researchers can focus on developing new ideas, collaborations and projects.
The proposed research project is a joint effort between Onera and ENAC. Our common research topics include UAVs systems, sustainable transportation development, and safety and security of cyber-physical systems. For further information, please consult our sites: ENAC , Onera.

References

[1] Schranz, Melanie, et al. "Swarm intelligence and cyber-physical systems: concepts, challenges and future trends." Swarm and Evolutionary Computation 60 (2021): 100762.
[2] Connor, Jack, Benjamin Champion, and Matthew A. Joordens. "Current algorithms, communication methods and designs for underwater swarm robotics: A review." IEEE Sensors Journal 21.1 (2020): 153-169.
[3] Ferreira, Bruno, et al. "A Lightweight Fluid Model for Mobile Ad hoc Distributed Systems." (2022).
[4] Alexandra de Cecco. "Modélisation Fluide de Réseaux. Modélisation et simulation" (Doctoral thesis). UNIVERSITE DE TOULOUSE; UT3, (2016).
[5] Ferrer, Ana Juan, et al. "Towards a cognitive compute continuum: an architecture for ad-hoc self-managed swarms." 2021 IEEE/ACM 21st International Symposium on Cluster, Cloud and Internet Computing (CCGrid). IEEE, 2021.
[6] Wu, Yu, et al. "Swarm-based 4D path planning for drone operations in urban environments." IEEE Transactions on Vehicular Technology 70.8 (2021): 7464-7479.

PhD position: Designing Distributed System for Mobile Computing (applications on IoT/drones)

Keywords: Distributed algorithms; queueing network model; parallel computing; computational fluid dynamics; edge computing; dynamic, mobile networks; differential equations; simulation

Context

The design of distributed systems has become increasingly important to provide reliable services with high availability. Most internet services rely on large amounts of resources of cloud-centric infrastructures to tolerate failures and enhance data availability to users. While such a cloud-centric design has been widely used to implement popular services, like video stores and social networking, this computing model alone is unlikely to fit well to emerging latency-critical applications on dynamic networks, such as mobile networks and wireless networks.
The growing popularity of cloud-centric distributed systems strongly relies on advances in hardware and software components of datacenters. For instance, Li et al. [1] propose a new high-performance replication protocol based on the assumptions that packet losses and reordering are rare inside datacenters. However, these assumptions are likely to be incorrect in dynamic networks.
In a dynamic network, such as a swarm of drones, the design of reliable distributed systems with high performance is challenging. System designers should cope with unstable, heterogeneous resources availability, eventually frequent network partitions and fast-changing data availability requirements. These limitations can lead to a dramatic performance degradation of the distributed system for clients of edge, mobile services.
Suitable techniques and algorithms are therefore required in order to guarantee high throughput and low latency for emerging distributed systems on dynamic networks.

Proposed research

This research project focuses on load balancing techniques and scheduling protocols for achieving high-performance, reliable distributed systems in dynamic networks.
The availability and fault tolerance of a reliable distributed system are commonly guaranteed by a replication protocol based on replicated state machine (RSM). Such a protocol implements a consensus algorithm, like Fast Paxos [2] and Raft [3], in order to provide strong consistency throughout distributed, replicated data. In fact, strongly consistent replication is key to efficient implementation of critical distributed systems' building blocks, like distributed lock manager or transactional key-value store.
The body of research effort on load balancing techniques and scheduling protocols has yielded significant performance gains in cloud-centric systems. Aspnes et al. [4] develop on-line load balancing techniques to minimize the maximum load of requests in distributed computing clusters. Regarding RSM, Alchieri et al. [5] propose a scheduling protocol that simplifies the work done by the scheduler while improving the performance of the system. Yet, further research is needed for evaluating these techniques and protocols in dynamic edge computing, where the availability of nodes' resources is barely unpredictable and the network topologies evolve continuously.
In order to provide a valuable trade-off between enforcing strong consistency and providing high-performance, we are highly interested in investigating new load balancing techniques and scheduling protocols for emerging mobile distributed systems. To conduct this exciting, promising research, we will combine ideas from two disciplines: distributed algorithms and computational fluid dynamics. Therefore, we intend to review the techniques to dynamically handle operations throughout moving replicas based on fast, advanced simulation of system messages flows to enforce ordering and timing constraints.

Requirements and application

In this research, we intend to explore both a fundamental and an applied aspects. In particular, we aim to run real experiments with fleet of unmanned aerial vehicles (UAVs), commonly known as drones, in the UAV experimental flight facility of our campus.
Candidates to this position should hold a Master's degree in Computer Science/Informatics, Mathematics, Physics or a related field by the starting date of the PhD. They must be excited by research in distributed systems, distributed algorithms, computational fluid dynamics, and/or programming languages, and should have an excellent academic record in one of these areas. Familiarity with queueing network model and differential equations would be appreciated. Teamwork and communication skills are key to this position, and industrial experience is a plus.
Knowledge of French is not required.
To apply, please send the following information to ds-resco-recruitment@lists.recherche.enac.fr(Subject=PhD position: Designing Distributed System for Mobile Computing):

  • Curriculum Vitæ
  • Letter of motivation that should describe the applicant's background in the areas of the project, reasons for interest in the project, and future plans
  • A list of courses and grades of the last two years of study (an informal transcript is enough).
  • Names and contact details of at least two people who can write you references, whom we will contact directly.
  • If relevant, a link to your publications and/or open-source developments.

Application deadline: 10 June 2019.
This fully-funded PhD starts on 1 October 2023 and the duration of the contract/scholarship is 3 years.

Eligibility criteria and Benefits

Applicants of any nationality can apply, but applicants must not have a doctoral degree already or been enrolled in a PhD/doctoral program.
Benefits include:

  • French government strongly subsidizes higher education, therefore the tuition fees are among the more competitive in Europe
  • Social security coverage included
  • Subsidized meals
  • Partial reimbursement of public transport costs
  • Social, cultural and sports events and activities

About Onera and ENAC research laboratories

Onera, the French Aerospace Lab, and ENAC, National School of Civil Aviation, are both located in Toulouse, France, the centre of the European aerospace industry. Our research laboratories offer ideal working environments, where researchers can focus on developing new ideas, collaborations and projects.
The proposed research project is a joint effort between Onera and ENAC. Our common research topics include UAVs systems, sustainable transportation development, and safety and security of cyber-physical systems. For further information, please consult our sites: ENAC , Onera.

References

[1] Li, J., Michael, E., Sharma, N. K., Szekeres, A., & Ports, D. R. (2016). Just say NO to Paxos overhead: replacing consensus with network ordering. In 12th USENIX Symposium on Operating Systems Design and Implementation (OSDI 16) (pp. 467-483).
[2] L. Lamport. Fast Paxos. (2006). Distributed Computing, 19(2).
[3] Ongaro, D., & Ousterhout, J. (2014). In search of an understandable consensus algorithm. In 2014 USENIX Annual Technical Conference (USENIX ATC 14) (pp. 305-319).
[4] Aspnes, J., Azar, Y., Fiat, A., Plotkin, S., & Waarts, O. (1997). On-line routing of virtual circuits with applications to load balancing and machine scheduling. Journal of the ACM (JACM), 44(3), 486-504.
[5] Alchieri, E., Dotti, F., & Pedone, F. (2018). Early scheduling in parallel state machine replication. In Proceedings of the ACM Symposium on Cloud Computing (pp. 82-94).