This book focuses on techniques that can be applied at the physical and data-link layers of
communication systems in order to secure transmissions against eavesdroppers. Topics ranging
from information theory-based security to coding for security and cryptography are discussed
with presentation of cutting-edge research and innovative results from leading researchers. The
characteristic feature of all the contributions is their relevance for practical embodiments:
detailed consideration is given to applications of security principles to a variety of widely
used communication techniques such as multiantenna systems ultra-wide band communication
systems power line communications and quantum key distribution techniques. A further
distinctive aspect is the attention paid to both unconditional and computational security
techniques providing a bridge between two usually distinct worlds. The book comprises extended
versions of contributions delivered at the Workshop on Communication Security held in Ancona
Italy in September 2014 within the framework of the research project Enhancing Communication
Security by Cross-layer Physical and Data-link Techniques funded by the Italian Ministry of
Education Universities and Research.
