Thursday, December 8

6:45 PM: Informal Dinner

We will organize an informal dinner. You are cordially invited to join us. The dinner place is Andalucia. It is in walking distance from the conference/workshop venue and takes approximately 15 minutes (directions from the venue). We will meet at the Hilton lobby around 6:30 pm, or join us directly at Andalucia around 6:45 pm. After dinner, there will be the opportunity to move to Flying Saucer, a fancy beer place.

Friday, December 9, Room: GRB 342 A/B

08:00 - 09:30

CCNet1: Complex Networks

Chair: Rong Zheng (University of Houston, USA)
Self-organization of Nodes Using Bio-Inspired Techniques for Achieving Small World Properties
Rachit Agarwal (Telecom SudParis & SAMOVAR UMR 5157, France); Abhik Banerjee (Nanyang Technological University, Singapore); Vincent Gauthier (Institut TELECOM; Telecom SudParis; SAMOVAR UMR, France); Monique Becker (Institut TELECOM; Telecom SudParis, France); Chai Kiat Yeo (Nanyang Technological University, Singapore); Bu Sung Lee (Nanyang Technological University, Singapore)
In an autonomous wireless sensor environment, self organization of the nodes is essential in order to achieve network wide characteristics. In wireless autonomous environment, we believe connectivity in wireless network can be increased and overall average path length can be reduced using beamforming and biologically inspired algorithms. "The emergence of system wide functionality from simple local interactions between individual entities" [1] inspires us to achieve our current goal. Recent researches performed in direction of beamforming in wireless networks mostly assume knowledge of network with the heterogeneous [2] or hybrid deployment [3]. We propose that without the knowledge of the global environment or introduction of any special features, average path length can be reduced with the help of inspirations from the nature. As well as the number of network components can be reduces in a sparsely connected network. We further support our work with results and show that average path length and the number of sub components can be reduced using very simple local rules and without the full network knowledge.
An Internet Local Routing Approach Based on Network Structural Connectivity
Pau Erola (Universitat Rovira i Virgili, Spain); Sergio Gómez (Universitat Rovira i Virgili, Spain); Alex Arenas (Universidad Rovira I Virgili, Spain)
Internet is one of the largest synthetic complex system ever built. It consists in a collection of more than 30,000 networks each one known as an Autonomous System. In the last few years, Internet is experiencing an explosive growth that is compromising its navigation scalability due to its dependence on the Border Gateway Protocol (BGP). The BGP routing protocol requires to maintain an updated partial view of the network topology, involving a huge amount of data exchange and significant convergence times. The scale-free topology of Internet makes complex network theory the natural framework to analyze its problems and propose solutions. Here, we present a local alternative to BGP based on complex networks. Our approach uses the linear projection of the modular structure of the network to construct a navigable map of the Internet. This map guarantees a high reliability over time on the actual evolving network, in the sense that projection changes are negligible. The simulation results show that we are in high percentage close to optimal paths.
Towards Community-Centric Integrity Management in Crowd-Sourced Systems
Amin Ranjbar (McGill University, Canada); Muthucumaru Maheswaran (McGill University, Canada)
Integrity is an important concern in any knowledge management system. This paper discusses an ongoing research work that aims to develop a community-centric integrity management system for a large-scale knowledge management system that works on the Internet.

09:30 - 10:00

Coffee Break

10:00 - 12:00

PerGroup1: Pervasive Group Communication

Chair: Thomas C. Schmidt (HAW Hamburg (DE), Germany)
Alleviating Network Load in Dense Urban Multi-Access Application-Layer Multicast
Christian Hübsch (Karlsruhe Institute of Technology (KIT), Germany); Oliver P. Waldhorst (Ilmenau University of Technology & Karlsruhe Institute of Technology (KIT), Germany)
Application-Layer Multicast (ALM) is a promising approach to overcome the lack of global IP Multicast availability. Since ALM protocols relieve load from centralized content servers and offer flexible group communication without requiring dedicated support in the network, they can be considered a viable solution for future content distribution. Anyway, using ALM in capacity-constrained environments like dense urban cellular networks may worsen congestions due to higher bandwidth consumption inside the access networks. In this paper, we propose the integration of multi-access communication in ALM in order to alleviate access networks from traffic load and avoid congestion. Doing so, we propose a two-step ALM building approach that first establishes a single-homed cellular overlay tree, before efficiently looking up and integtrating alternative WiFi communication possibilities in the dissemination tree. Finding WiFi peers in range is not trivial in dense urban environments, since the number of concurrently visible public WiFi domains may be high and Ad-hoc scanning should be avoided if possible to save energy. Our proposal follows a space-efficient Bloom Filter-based technique, allowing to precisely join public Wifi domains with high chance of meeting foreign peers without having to try out several candidate domains first.
Service Sharing in Mobile Sensing Systems
Pramita Mitra (University of Notre Dame, USA); Christian Poellabauer (University of Notre Dame, USA)
Today's modern mobile devices, (such as smartphones and tablets) present great potential for growth of many novel, powerful, but also highly demanding applications. However, most mobile devices/users operate in isolation from one another, i.e., they are not aware of the presence of other devices in their proximity. There are numerous situations where proximity-awareness (i.e., a device is aware of other mobile devices in its neighborhood) could be used to support spontaneous sharing of resources and information, thereby enabling a variety of new application scenarios. This paper presents an architecture, called SPontaneous Information and Resource sharing InfrasTructure (SPIRIT), that allows mobile devices to create, discover, join, leave, and revoke the sharing of resources in an efficient and robust fashion. Built on top of a group communications layer for mobile devices, SPIRIT allows users or devices to express various heterogeneous services and service sharing paradigms using a novel subscription language. While the shared services can include various types of resources (e.g., network connections, CPU) and information (e.g., database entries), this paper's focus is on sensor information, i.e., the information collected by the various sensors found in modern mobile devices (e.g., GPS, acceleration, light, pressure, sound, etc.).
Group-based Underwater Wireless Sensor Network for Marine Fish Farms
Jaime Lloret (Universidad Politécnica de Valencia, Spain); Sandra Sendra (Universidad Politécnica de Valencia, Spain); Miguel Garcia (Universidad Politecnica de Valencia, Spain); Ginés Lloret (Instituto Politécnico Marítimo Pesquero del Mediterraneo, Spain)
The amount of uneaten feed and fecal waste generated by the fish in marine fish farms causes the damage of the fauna and flora, and it also reduces the economic benefits because the wastage of the uneaten food. In this paper, we propose an underwater group-based sensor network in order to quantify accurately the amount of pollution deposited on the seabed. First, an analytical model let us know the best location to place the sensor nodes. Our group-based wireless sensor network (WSN) proposal could also determine the amount of food that is wasted while it measures the amount of deposits generated. We describe the mobility of the nodes and how operates the group-based protocol and we show several simulations in order to view the load traffic and to verify the correct operation of the WSN.
A Markovian Model for Evaluating the Performance of a Key Management Scheme
Hani Ragab-Hassen (University of Kent, United Kingdom); Imed Romdhani (Edinburgh Napier University, United Kingdom)
Content access control aims at ensuring that in a system with several resources, users can access only resources to which they are authorized. Resources are encrypted using cryptographic keys. Generating, distributing and renewing these keys are the challenges faced by key management schemes. While most of the existing key management schemes are typically evaluated by either complexity calculation or simulation, we propose to use Markovian processes for this purpose. We start by describing the content access control problem and we give an overview of the existing key management schemes. Thereafter, we focus on Hi-KD (Hash-based Hierarchical Key Distribution) which is a particularly interesting key management scheme. Hi-KD requires that each user maintains a set of keys. The size of this set changes randomly making the evaluation of the overhead of Hi-KD more complicated than for other key management schemes. We model and evaluate the key storage and computation time of Hi-KD using a Markov process.

12:00 - 13:30

Lunch Break

13:30 - 14:30

CCNet3: Complex Networks

Chair: Rong Zheng (University of Houston, USA)
Self-Organization of Wireless Ad Hoc Networks as Small Worlds Using Long Range Directional Beams
Abhik Banerjee (Nanyang Technological University, Singapore); Rachit Agarwal (Telecom SudParis & SAMOVAR UMR 5157, France); Vincent Gauthier (Institut TELECOM; Telecom SudParis; SAMOVAR UMR, France); Chai Kiat Yeo (Nanyang Technological University, Singapore); Hossam Afifi (Institut Telecom & Paris South, France); Bu Sung Lee (Nanyang Technological University, Singapore)
We study how long range directional beams can be used for self-organization of a wireless network to exhibit small world properties. Using simulation results for randomized beamforming as a guideline, we identify crucial design issues for algorithm design. Subsequently, we propose an algorithm for deterministic creation of small worlds. We define a new centrality measure that estimates the structural importance of nodes based on traffic flow in the network, which is used to identify the optimum nodes for beamforming. This results in significant reduction in path length while maintaining connectivity.
Analysis of Academic Ties: A Case Study of Mathematics Genealogy
Engin Arslan (University of Nevada, Reno, USA); Mehmet Hadi Gunes (University of Nevada, Reno, USA); Murat Yuksel (University of Nevada - Reno, USA)
Analyzing social networks of communities helps us obtain local and large-scale information about the social relations. We can also observe how structural as well as behavioral changes occur among the members of a social network over years. In this paper, we analyze academic ties of mathematicians using the Mathematics Genealogy Project data. Additionally, using university and nation information of mathematicians, we examined which universities or nations are more correlated as well as how these correlations change over the years

14:30 - 16:00

CCNet2: Potpourri

Chairs: Matthias Wählisch (Freie Universität Berlin, Germany), Rong Zheng (University of Houston, USA)
Novel Path Protection Scheme for Multi-Domain Networks
Feng Xu (University of New Mexico, USA); Feng Gu (University of New Mexico, USA); Hamed M. K. Alazemi (Kuwait University, Kuwait); Min Peng (Wuhan University, P.R. China); Nasir Ghani (University of New Mexico, USA)
Network survivability remains a major concern and operators have considered a range of pre-provisioned protection strategies for single link failures. As services expand, there is a further need to extend such strategies across multiple network domains. Nevertheless, this is a very complex problem as computation and setup of diverse path pairs across domains is much more challenging given reduced state visibility between domains. Hence most schemes have either focused on restrictive per-domain protection schemes. To address these challenges, this paper proposes a novel distributed multi-domain protection solution that achieves varying levels of primary/backup separation with notably lower routing overhead complexity. The solution is evaluated in detail using simulation.
Packet Reordering in TCP
Per Hurtig (Karlstad University, Sweden); Anna Brunstrom (Karlstad University, Sweden)
Packet reordering is now considered naturally prevalent within complex networks like the Internet. When packets are reordered, the performance of transport protocols like TCP is severely hurt. To overcome performance issues a number of mitigations have been proposed. While evaluations have shown the success of such mitigations, most have not considered realistic scenarios where other impairments are present. Furthermore, most studies only evaluate the performance long-lived TCP flows, although short-lived flows are the most common. In this paper we evaluate Linux's built-in reordering mitigation and the TCP-NCR proposal using real protocol implementations. The results show that Linux and TCP-NCR are able to provide good protection against reordering when no other impairments are present. For flows that also experience packet loss, the performance is dominated by the negative effect of these losses. Results also indicate that short-lived flows are sensitive to how reordering mitigation is conducted. Linux was able to improve the performance of short flows slightly, while TCP-NCR performed worse than TCP without reordering protection.
Routing, Weight Assignment and Load Balancing for Tunnel-based Fast IP Local Failure Recovery
Po-Kai Tseng (Academia Sinica, Taiwan); Wei-Ho Chung (Academia Sinica, Taiwan)
To alleviate the impact of network component failures, many fast IP local recovery schemes have been proposed to reroute traffic in the event of failure. Tunnel-based fast IP local recovery is one of the most commonly adopted techniques. In IP-in-IP tunneling, when a failure occurs, the nodes adjacent to a failure are activated to encapsulate and reroute the affected traffic to the endpoint along the shortest path. Once the endpoint receives the affected traffic, it decapsulates and delivers the packets to original destination along the shortest path. These shortest paths are computed based on link weights. Therefore the design of link weights for tunnel-based fast IP local recovery is a critical issue. The goal of this paper is to determine a set of link weights in a tunnel-based fast IP local recovery system to jointly achieve: (1) load balance in the normal state (i.e., non-failure state) and (2) protection of any single link failure without incurring link overload during the failure recovery. We first formulate this problem as a mixed integer programming (MIP). Due to the NP-hard property of the MIP, a Simulated Annealing based Tunneling (SATu) scheme is proposed to obtain the solution of the MIP. In SATu, only the nodes adjacent to a failure are activated to encapsulate the affected packets and forward them to endpoint without disturbing regular traffic. Numerical results delineate that the proposed scheme improves tunnel-based IP fast reroute approach to achieve high rate of fault recovery in protecting single link failures without incurring link congestion in the non-failure state.