  One of the most important goals of the 21st century is to change radically
the way our society produces and distributes energy. This broad objective
embodies in the smart grid's futuristic vision of a completely decentralized
system powered by renewable plants. Imagine indeed such a real time power
network in which everyone could be a consumer or a producer. Based on a coupled
information system, each user would be able to buy or sell energy at a time
depending price that would allow a homogenization of the consumption,
eradicating the well known morning or evening peak. This attractive idea is
currently booming in the scientific community as it generates intellectual
challenges in various domains.
  Nevertheless, lots of unanswered questions remain. The first steps are
currently accomplished with the appearance of smart meters or the development
of more efficient energy storage devices. However, the design of the
decentralized information system of the smart grid, which will have to deal
with huge amounts of sensor's data in order to control the system within its
stability region, seems to be still in search.
  In the following survey, we concentrate on the telecommunication part of the
smart grid system. We begin by identifying different control level in the
system, and we focus on high control levels, which are commonly attributed to
the information system. We then define a few concepts of the smart grid and
present some interesting approaches using models from the complex system
theory. In the last part, we review ongoing works aiming at establishing
telecommunication requirements for smart grid applications, and underline the
necessity of building accountable models for testing these values.
