Complex networks, including the Internet, wireless and cellular networks, and on-line social networks, are becoming indispensable parts of our daily lives. These networks arising from a wide range of applications can be represented and studied as graphs, and the underlying link patterns play an important role in understanding and solving problems in such applications. For example, many online social networks, such as Twitter and Google+, can be viewed as directed graphs with uni-directional "following'' relations among users, and the link directions contain crucial information about how users form social communities. In another application, online social networks such as Slashdot and Epinions represent relationships between users as links with positive or negative weights, which correspond to friend and foe relations. These networks are referred to as signed networks, where those signed links generate new challenges in understanding and studying the underlying network properties. In this talk, I present my work on developing theories for studying and characterizing various crucial graph properties, such as the edge directionality in directed graphs and the edge polarity in signed graphs. I do so by emphasizing on applications to detecting stable social communities and understanding social influence propagation patterns on online social networks.

On Jan 8-9, 2013, the kick-off meeting of Research & Development project CROWD (Connectivity management for eneRgy Optimised Wireless Dense networks) was held in Pisa (Italy). CROWD is co-funded by the European Commission within the Seventh Framework Programme (FP7).

Energy conservation is drawing increasing attention in data networking. One school of thought believes that a dominant amount of energy saving comes from turning off network elements. The difficulty is that transitioning between the active and sleeping modes consumes considerable energy and time. This results in an obvious trade-off between saving energy and provisioning performance guarantees such as end-to-end delays.

Arturo Azcorra presentará cuáles son, en su experiencia personal, las mejores prácticas para la redacción de un documento técnico. La conferencia cubrirá algunas ideas a seguir y algunos problemas a evitar al escribir un artículo.

​With an optimistic assumption that a WiFi Access Point (AP) is idle for 50% of the time, an approximate energy waste caused exclusively by WiFi APs worldwide is estimated to be a striking 4.7 Billion KWh/year. Furthermore, many other types of future wireless network devices are expected to spend substantial amounts of energy in their idle listening modes, including wireless sensor and actuator nodes, wireless smart meters, mobile phones, and cellular base stations.

The Internet has transformed itself into a critical global information infrastructure, and fundamentally altered the ways we access information, communicate and interact with each other, purchase goods and services, and entertain ourselves. Despite its enormous success, the Internet suffers certain well-known shortcomings, and is increasingly strained to meet the high availability, reliability, mobility, manageability and security demands of Internet applications, users, and service providers alike. Much of my research is centered on addressing the challenges posed by these new demands.

In this talk, I will discuss the complex relationship between the university research lab and the startup community and how it varies in different places. There will be some emphasis on software focused startups as these are quite special in terms of the low capital investment costs required to deliver an initial working product, but the talk will also consider the wider set of high tech startup enterprises, some of which are built on a deep understanding of a problem domain arising from substantial research. The talk will discuss the similarities and differences between the activities and skills of the research lab and the startup.

Mobile phones and tablets can be considered as the first incarnation of the post-PC era. Their explosive adoption rate has been driven by a number of factors, with the most significant influence being touch-screens, sensors, app markets, and better cellular technologies.

Economic forces behind the Internet evolution have diversified the types of ISP (Internet Service Provider) interconnections. In particular, settlement-free peering and paid peering proved themselves as effective means for reducing ISP costs. In this paper, we propose T4P (Transit for Peering), a new type of hybrid bilateral ISP relationships that continues the Internet trend towards more flexible interconnections at lower costs.

In this self-contained talk I will describe few combinatorial results that were initiated by problems from several application areas. These results include the following: (1) the use of the Cycle Lemma in deriving statistics about several classes of trees (this includes, as a start, a very simple proof for the Catalan number of binary trees), (2) a new characterization of tree medians, (3) an algorithm for generation of permutations, (4) a result about the volume of discrete spheres, and (5) a combinatorial problem that resulted in a paper with
Paul Erdős