Xavier Sanchez-Loro

Ubiquitous Web Access: Collaborative Optimization and Dynamic Content Negotiation

Traditionally, cellular wide area networks like UMTS are used as Internet access networks for particular users but, in some cases, they can be employed to provide Internet access to other smaller networks as well. The main inconvenient is that cellular networks have not the same bandwidth than wired networks and therefore, the cellular channel becomes a network bottle-neck. To help to mitigate this situation and in order to improve the users experience different optimization techniques exist, especially in web traffic. This paper studies first the existing synergies at HTTP layer between device capabilities expression, content negotiation, channel optimization and content adaptation. And secondly, it presents a system where HTTP requests transmission is optimized, showing a significant improvement in response time by means of HTTP header reduction over the cellular channel. In order to obtain a successful browsing experience, headers should be restored when reaching the Internet. This dynamic header reconstruction allows giving enriched and more expressive information about users device and browser capabilities. Thus navigation speed and users QoE can be enhanced by means of dynamic content negotiation in order to obtain adapted (and lighter) content and responses from web servers and adaptation proxies alike.

Proposal of a clean slate network architecture for ubiquitous services provisioning

The Pervasive Computing field is almost always addressed from application, middleware, sensing or Human Computer Interaction perspective. Thus, solutions are usually designed at application level or involve developing new hardware. Although current layered network architectures (mainly TCP/IP stack) have enabled internetworking of lots of different devices and services, they are neither well-suited nor optimized for pervasive computing applications. Hence, we firmly believe that we should have an underlying network architecture providing the flexible, context-aware and adaptable communication infrastructure required to ease the development of ubiquitous services and applications. Herein, we propose a clean slate network architecture to deploy ubiquitous services in a Pervasive and Ubiquitous Computing environment. The architecture is designed to avoid hierarchical layering, so we propose a service-oriented approach for a flow-oriented context-aware network architecture where communications are composed on the fly (using reusable components) according to the needs and requirements of the consumed service.

A Proxy-Based System For Dynamic Content Negotiation And Collaborative Optimization In Heterogenic Environments

Abstract Ubiquitous and Pervasive Computing relies on ubiquitous network access and applications’ context-awareness. This pervasive access implies exchanging traffic with a wide spectrum of devices across heterogenic networks. Services and applications deployed on these networks should adapt its operation and presentation to the characteristics of the underlying network technologies and the actual client device capabilities. Cellulaz wide azea networks like UMTS are used as Internet access networks for particular users but, in some cases, they can also be employed to provide Internet access to other smaller networks. The main inconvenient is that cellular networks have not the same bandwidth as wired networks and therefore, the cellular channel becomes a network bottle-neck. To help to mitigate this situation and in order to improve the user’s experience different optimization techniques exist, especially in web traffic. This paper studies the existing synergies at HTTP layer between device capabilities e...

Ubiquitous Web Access and Application Layer Optimization: Dynamic Content Negotiation over Cellular Links

Cellular wide area networks like UMTS can be employed to provide Internet access to other smaller networks. The main inconvenient is that cellular networks have not the same bandwidth than wired networks and therefore, the cellular channel becomes a network bottle-neck. To help to mitigate this situation different optimization techniques exist, especially in Web traffic. Herein we present a system where HTTP requests transmission is optimized over the cellular channel by means of header reduction. In order to obtain a successful browsing experience, headers should be restored when reaching the Internet. Thus, we took in advantage of the need for header browser profiling to integrate in the system a device capabilities detection service. This service allows giving enriched information about users device and browser capabilities; enhancing navigation speed and users QoE by means of dynamic capabilities expression in order to obtain adapted responses from Web servers and adaptation proxies alike.

Rate adaptation in 3GPP video streaming using track switching over a multihop WLAN

In nowadays communication technologies, one of the main challenges to overcome is how to translate theoretical algorithms, designed protocols, existing hardware products from different manufacturers and the already knowhow into innovative applications that can produce a benefit for the user and for the commercializing firm. Following this topic, the present paper introduces an application that combines different emerging technologies: wireless mesh networks, multihop routing and adaptation of streaming delivery with the objective to create a tool for effective marketing campaigns.

Implementation of Context-Aware Network Architecture for Smart Objects Based on Functional Composition

Lack of flexibility of current Internet architecture led researchers to come up with new paradigms for a novel Internet architecture, which would be able to reduce complexity and increase flexibility compared to current Internet architecture. Functional co mposition is a promising approach to flexible and evolvable architecture design. The idea is composing complex protocol suites by dynamically bind and arrange different functions to obtain certain behavior. Herein, we present the implementation of a contex t - aware network architecture based on functional composition for smart objects. A sub - set of those basic functional blocks has been implemented and validated on an experimental testbed using different network topologies .

Optimizing the delivery chain in heterogenous networks

Herein, we will focus on proposing a service taxonomy and classification for RBA/SOA architectures aiming to model a common framework for the description and composition of possible Atomic Services or networking functions valid for architectures coping with heterogenous environments. The final objective is fine-tuning the delivery chain to optimize application and delivery performance and behaviour in heterogenous networks. Although our work takes the TARIFA architecture as the basis model for our contribution, we think it can be helpful for other architectures dealing with protocol modularization and service composition.