Publications by Julien Pierre Sacha Herzen

Csma/ca in time and frequency domains

Patrick Thiran, Julien Pierre Sacha Herzen

The present invention concerns a method for a communication device to transmit a data packet in a wireless communication system. The method comprises: determining (21) a first set of transmission parameters comprising a first central transmission frequency ...

2017

How CSMA/CA With Deferral Affects Performance and Dynamics in Power-Line Communications

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

Power-line communications (PLC) are becoming a key component in home networking, because they provide easy and high-throughput connectivity. The dominant MAC protocol for high data-rate PLC, the IEEE 1901, employs a CSMA/CA mechanism similar to the backoff ...

Ieee-Inst Electrical Electronics Engineers Inc2017

EMPoWER Hybrid Networks: Exploiting Multiple Paths over Wireless and ElectRical Mediums

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou, Sébastien Christophe Henri

Several technologies, such as WiFi, Ethernet and power-line communications (PLC), can be used to build residential and enterprise networks. These technologies often co-exist; most networks use WiFi, and buildings are readily equipped with electrical wires ...

2016

Analysis and Enhancement of CSMA/CA With Deferral in Power-Line Communications

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

Power-line communications are employed in home networking to provide easy and high-throughput connectivity. The IEEE 1901, the MAC protocol for power-line networks, employs a CSMA/CA protocol similar to that of 802.11, but is substantially more complex, wh ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Flexible Spectrum Assignment for Local Wireless Networks

Julien Pierre Sacha Herzen

In this dissertation, we consider the problem of assigning spectrum to wireless local-area networks (WLANs). In line with recent IEEE 802.11 amendments and newer hardware capabilities, we consider situations where wireless nodes have the ability to adapt n ...

EPFL2015

CSMA/CA in Time and Frequency Domains

Patrick Thiran, Julien Pierre Sacha Herzen

It has recently been shown that flexible channelization, whereby wireless stations adapt their spectrum bands on a per-frame basis, is feasible in practice. In this paper, we propose TF-CSMA/CA, an algorithm for flexible channelization that schedules packe ...

IEEE2015

Learning Wi-Fi Performance

Julien Pierre Sacha Herzen, Nidhi Hegde

Accurate prediction of wireless network performance is important when performing link adaptation or resource allocation. However, the complexity of interference interactions at MAC and PHY layers, as well as the vast variety of possible wireless configurat ...

IEEE2015

Method to optimize the communication parameters between an access point and at least one client device

Patrick Thiran, Ruben Merz, Julien Pierre Sacha Herzen

A method to optimize the communication on a channel between an access point and at least one client device, said channel being characterized by a center frequency and a bandwidth, comprises: establishing a connection on a first channel according to a first ...

2014

Mining Democracy

Patrick Thiran, Matthias Grossglauser, Vincent Etter, Julien Pierre Sacha Herzen

Switzerland has a long tradition of direct democracy, which makes it an ideal laboratory for research on real-world politics. Similar to recent open government initiatives launched worldwide, the Swiss government regularly releases datasets related to stat ...

2014

Performance Analysis of MAC for Power-Line Communications

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

We investigate the IEEE 1901 MAC protocol, the dominant protocol for high data rate power-line communications. 1901 employs a CSMA/CA mechanism similar to – but much more complex than – the backoff mechanism of 802.11. Because of this extra complexity, and ...

2014

On the MAC for Power-Line Communications: Modeling Assumptions and Performance Tradeoffs

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

Power-line communications are becoming a key component in home networking. The dominant MAC protocol for high data-rate power-line communications, IEEE 1901, employs a CSMA/CA mechanism similar to the backoff process of 802.11. Existing performance evaluat ...

2014

Analyzing and Boosting the Performance of Power-Line Communication Networks

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

Power-line communications are employed in home networking to provide easy and high-throughput connectivity. IEEE 1901, the MAC protocol for power-line networks, employs a CSMA/CA protocol similar to that of 802.11, but is substantially more complex, which ...

2014

Distributed Spectrum Assignment for Home WLANs

Patrick Thiran, Ruben Merz, Julien Pierre Sacha Herzen

We consider the problem of jointly allocating chan- nel center frequencies and bandwidths for IEEE 802.11 wireless LANs (WLANs). The bandwidth used on a link affects sig- nificantly both the capacity experienced on this link and the interference produced o ...

2013

Fairness of MAC protocols: IEEE 1901 vs. 802.11

Patrick Thiran, Julien Pierre Sacha Herzen, Christina Vlachou

The MAC layer of the IEEE 1901 standard for power line communications employs a CSMA/CA method similar to, but more complex than, this of IEEE 802.11 for wireless communications. The differences between these protocols raise questions such as which one per ...

IEEE2013

Scalable Routing Easy as PIE: a Practical Isometric Embedding Protocol

Patrick Thiran, Julien Pierre Sacha Herzen

We present PIE, a scalable routing scheme that achieves 100% packet delivery and low path stretch. It is easy to implement in a distributed fashion and works well when costs are associated to links. Scalability is achieved by using virtual coordinates in a ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2011

Enhance & Explore: an Adaptive Algorithm to Maximize the Utility of Wireless Networks

Patrick Thiran, Ruben Merz, Adel Aziz, Julien Pierre Sacha Herzen

The goal of jointly providing efficiency and fairness in wireless networks can be seen as the problem of maximizing a given utility function. In contrast with wired networks, the capacity of wireless networks is typically time-varying and not known explici ...

2011

Demo Abstract of Net-Controller: a Network Visualization and Management Tool

Patrick Thiran, Adel Aziz, Julien Pierre Sacha Herzen

Net-Controller is a user-friendly network visualization and management tool developed at EPFL in order to easily retrieve and display in real time network statistics, such as link throughput and queue occupancy from a large testbed composed of wireless rou ...

2010