Guest Editorial: Network science

A recent topic of research in the network science community is combined or composite networks - these are two or more interacting networks that must be characterized jointly rather than individually. For example, a social network and a communication network sharing some nodes (corresponding to users) may be modeled together as a composite network. This may be useful since the aggregate performance of a composite network may often depend on how the individual networks influence each other. Information may travel faster or slower through composite networks depending on how they are coupled. The above vision was captured in the Call for Papers for this special issue in the IEEE Journal On Selected Areas In Communications, and it was published in June 2012. As a result of this solicitation, we received 62 submissions by the deadline of August 15, 2012. Papers were selected after two rigorous rounds of review. The first round of notifications were sent out on December 17, 2012 to the authors whose papers passed the first round of review. Revised versions of the papers were submitted on January 31, 2013. Finally, after a second round of review, the Guest Editorial board decided on March 12, 2013 to accept 16 high quality papers for publication in this competitive special issue. Papers appearing in this special issue belong to five broad themes, which are not necessarily mutually exclusive: (1) fundamental principles in network science, (2) information propagation models in networks, (3) bringing insights from other genres of networks, (4) economic and game theoretic models, and (5) application of network science principles to communications networking problems.