Editorial

It is my privilege to welcome you to the inaugural issue of Photonic Network Communications. The primary goal of this journal is to publish scienti®c articles focusing on activities in research and development related to all-optical communication networks. For years, telecommunication networks have continuously been driven into new technology generations. This pace has increased dramatically due to signi®cant technological progress and a rich variety of communication services as well as rapidly expanding traf®c volume and growing demand for network ̄exibility and availability. With photonic networks, a new, highly promising age of communication appears on the horizon. Affordable broadband communications may soon become reality for everyone. Photonic networks exhibit novel properties such as optical transparency over large distances, nearly unlimited transmission capacity, transmissions with extremely low bit-error rates and a hitherto unmatched ̄exibility in operation. A powerful, universal communication structure is developing. Existing networks and the wealth of different communication services can be integrated naturally. In addition, the same optical infrastructure can, for instance, also be exploited for the terrestrial part of mobile communications, for highway and air-traf®c control systems as well as for analog and digital TVdistribution networks. The role that photonic technology will play in the development of future integrated broadband communications networks is being widely recognized. This is re ̄ected in the rapidly increasing number of related activities around the world. In the European program, RACE (Research on Advanced Communications in Europe), there were thirty-six projects on a variety of key aspects of photonic networks. In the current program, ACTS (Advanced Communications Technologies and Services), thirty-four projects involved photonic road maps, technologies, and networking. The Defense Advanced Research Projects Agency (DARPA) in the United States promotes the development of Gbit/s testbeds and alloptical networks in a similar manner. In Japan, many highly-ranked projects abound. The number of overviews, books and special issues published each year on photonic networks and photonic device technology increases steadily. Many international meetings and conferences are held on this particular subject. Conferences dedicated to communications devote several sessions to photonic networks. All major companies in the communications industry and many universities demonstrate their interest by developing photonic system and network prototypes (as well as initial products), by investing in photonic device research, or by exploring architecture and operation of photonic networks. The interest in photonic networks is essentially driven by ®ve factors: (1) electronic components typically handle transmission rates of up to a few tens of Gbit/s, whereas a single optical ®ber and passive optical devices are capable of supporting many Tbit/s; (2) impressive progress has been made in photonic device technology; (3) long-term traf®c volume suggests the exploitation of photonic technology; (4) ̄exibility provided by photonic networks have many advantages in network operation and maintenance; (5) and optical transparency provides future-proof investments and allows improved ̄exibility for introducing new services without disrupting existing network operation.