Logo ISAE3
FR |

lundi 20 octobre 2014.

Prof. Emmanuel Lochin received his Ph.D from the LIP6 laboratory of Pierre and Marie Curie University - Paris VI in December 2004 and the Habilitation Thesis (Habilitation à Diriger des Recheches) in October 2011 from Institut National Polytechnique de Toulouse (INPT) (Thesis, Slides). From July 2005 to August 2007, he held a researcher position in the Networks and Pervasive Computing research program at National ICT Australia, Sydney. He joined ISAE in September 2007 as researcher and network security officer. He is member of TéSA laboratory and networking expert in the TeSA scientific committee.

His main research domain deals with Satellite Networking and his research interests include DTN, Transport Protocols, Reliability, Erasure Coding, Congestion Control.

Program Committee Membership :

 Last news


I am mostly involved in the DTN area and in particular, I study congestion, the use Network Coding for IP networks and reliable mechanisms for long delay and satellite links.

See my publications for further details.

TETRYS : reThinking rEliabiliTy foR long-delaY networkS

TETRYS enables a new reliability algorithm specifically useful when retransmission is either problematic or not possible. In case of multimedia or multicast communications and in the context of the Delay Tolerant Networking (DTN), the classical retransmission schemes can be counterproductive in terms of data transfer performance or not possible when the acknowledgment path is not always available. Indeed, over long delay links, packets retransmission has a meaning of cost and must be minimized. The purpose of Tetrys is to propose a novel reliability mechanism with an implicit acknowledgment strategy that could be used either within these new DTN proposals, for multimedia traffic or in the context of multicast transport protocols. This proposal is based on a new on-the-fly erasure coding concept specifically designed to operate efficient reliable transfer over bi-directional links. Tetrys allows to unify a full reliability with an error correction scheme. Tetrys is not sensitive to the loss of acknowledgments while ensuring a faster data availability to the application compared to other traditional acknowledgment schemes. See this paper for detail :

More information available on the projetc website : TETRYS

Jungle Networking

Recent theoretical works, investigating the possibility to dispense the Internet with end-to-end congestion control, demonstrate that this new paradigm seems to be sustainable for the Internet and would not lead to a congestion collapse. Unlike congestion-controlled networks that depend on end-hosts to achieve the max-min-fairness, over anarchical networks, the traffic assignment is network based. This allows to be robust to network attacks or misbehaving end-hosts. However, the price of this anarchy is that loss recovery should be done with an ideal erasure coding scheme.

In this context we propose DeCongestion Transport Protocol (DCTP), a transport protocol based on Tetrys erasure coding scheme to perform over anarchical networks. We evaluate this protocol over a realistic ISP topology and show that : 1) the efficiency of such networks remains close to TCP ; 2) they support small buffer size which is a key property for optical networks and 3) real-time flows can be supported while reducing the end-to end-delay in the case of small buffer size.

See our presentation here

New Satellite Access Methods to Provide Internet Access to Under-Privileged Communities

A common DVB-RCS system profile utilises a fixed-rate time-division multiplexed forward satellite link using DVB-S2. Capacity in the return link is not dedicated but shared using Radio Resource Management (RRM). Individual RCSTs transmit using MF-TDMA. Allocations may employ a static pre-assigned transmission rate (based on a Service Level Agreement), or may be allocated in response to either explicit capacity requests or dynamically predicted traffic characteristics. Usually a combination of the three methods is used to seek a compromise between offered Quality of Service and efficient use of the satellite capacity. The time between requesting capacity and being granted capacity is usually kept low. In this proposal we would like to explore some innovative methods of satellite access and answer to the following questions :

  1. Can we specifically look at the use of Lower than Best Effort (LBE) service to provide differentiated services where the resulting traffic from the users’ terminals are assigned a LBE priority ? Current applications have been architected to work (at least) on the BE nature of the Internet. Hence it is important for us to evaluate the performance of current Internet applications when provided with LBE service and to understand the implications on the transport layer performance.
  2. Can we provide Internet access to users’ terminals by distributing the unused capacity ? The method of asking for capacity and being granted capacity (the RRM method) of the DVB-RCS satellite system provides the feasibility of engineering a system that could provide free access to communities by distributing the unused spectrum. The network providers could provide the notion of unsubscribed terminals which can be connected to the satellite network. These unsubscribed terminals can then request for capacity when they have data to send. However, the NCC would only grant capacity when there is a portion of the unused capacity that could be distributed over several of such terminals. Some of the research questions that need to resolved are :
    • We need to explore methods to support efficient use of spare spectrum for e.g. how should the NCC allocate the spare spectrum between unsubscribed terminals.
    • We need to explore whether the unsubscribed terminals experience additional delay compared to subscribed terminals and if so how does the delay vary for different traffic loads. Does the time between requesting for spare capacity and being granted capacity going to be high (in the order of several seconds, minutes or sometimes hours) ? If so, we may need to look at new network and transport methods to support such a system for e.g. we may need to explore the possibility of integrating the use of Delay Tolerant Network (DTN) into satellite terminals and the GW. The entire research would be carried through a mix of simulations using the ns-2 simulator as well as using the Platine DVB-RCS testbed.

Multipath Networking at Transport Layer

Conjointly with NICTA, we are exploring multipath transport protocols capabilities and in particular, we investigate possible enhancements in the CMT-SCTP protocol. This work is a part of the thesis of Golam Sarwar and a presentation of the expected thesis work is given in these slides.

DQN : DTN-routing over Quasi-Deterministic topology

This project proposes a novel DTN routing algorithm, called DQN, specifically designed for quasi-deterministic networks with an application to satellite constellations. A first study has demonstrated that DQN efficiently forwards the information over a satellite network derived from the Orbcomm topology while keeping a low replication overhead compare to all other well-known DTN routing schemes. This work has been done in the context of the PhD thesis of Rémi Diana. Check our publications for further details.

Projects and softwares

For other projects and softwares see check this page.

Some videos linked to my research activity


Université Pierre et Marie Curie, Université de la Réunion, Université de Franche-Comté, Université de Nice, Telecom Bretagne, University of New South Wales, NICTA, 7-IP, Thales Alenia Space, CNES

 Honors and Awards

IEEE Communications Letters exemplary reviewer 2013

I am, with Guillaume Jourjon and Patrick Sénac, the recipient of the best paper award of the Multimedia Communications & Home Services Symposium of IEEE International Conference on Communications (IEEE ICC 2007) Glasgow, UK - 24-27 June, 2007

Mention spéciale du jury CFIP2009 à Pierre Ugo Tournoux, CNRS-LAAS et Université de Toulouse pour son article avec Amine Bouabdallah, Emmanuel Lochin et Jérôme Lacan. Tetrys : Un mécanisme de fiabilisation polyvalent


- 1MTP2 : Computer Science Basis (concepts informatiques de base)
- 1SYS1 et 2SYS6 : Java System Programming (programmation des systèmes en Java)

- 5-12 MIN 327 : Networks
- 5-12 MIN 330 : Evaluation de performance
- 5-13 MIN 424 : Réseaux et protocoles de communications

 PhD and postdoc students

On going

- Guillaume Smith, thèse en co-tutelle NICTA/TéSA, Enabling Private Real-Time Applications by Exploiting the Links Between Erasure Coding and Secret Sharing Mechanisms
- Victor Alejandro Ramiro Cid, thèse en co-tutelle ISAE/NICTA, DTN monitoring
- Si Quoc Viet Trang, thèse co-financée CNES/TAS, Approches LBE sur lien satellite
- Gwilherm Baudic, thèse MENRT, Méthodologie d’émulation de réseaux DTN/DSN


- Golam Sarwar, Analysis and Design of Multipath Transport Protocols, co-tutelle NICTA-ISAE, the 9th July 2014. Golam is Chief Security Engineer at Vysk Communications Inc
- Nicolas Kuhn Intéractions inter-couches et liens à long délai : mécanismes de la couche liaison et performances de TCP thèse soutenue le 21 novembre 2013, Nicolas est en post-doctorat à Telecom Bretagne
- Rémi Diana, Routing based congestion control for DTN satellite topology - Routage à contrôle de congestion pour les réseaux DTNs thèse co-financée CNES/TéSA, soutenue le 6 décembre 2012, Rémi est ingénieur chez Amadeus SAS
- Pierre-Ugo Tournoux, Protocoles de transports basés sur le Network Coding, thèse LAAS-ISAE, décembre 2010, Pierre-Ugo est maître de conférences à l’université de La Réunion depuis Septembre 2012
- Dino Matin Lopez Pacheco post-doctorat ISAE Septembre 2008 à Aout 2009. Dino est maître de conférences à l’université de Nice depuis Septembre 2009
- Guillaume Jourjon Towards a Versatile Transport Protocol, thèse de l’université du New South Wales (UNSW) et de l’Université de Toulouse, Janvier 2008. Guillaume est maintenant chercheur à NICTA

SPIP | | Suivre la vie du site RSS 2.1