Abstract

Since the dawn of the internet technology, we have witnessed an unexpected increase in the network traffic volumes and capacity demand. During the same time, the telecommunication market became highly competitive. To cope with this situation and the new challenges, network operators continuously try to increase their network efficiency. By adopting WDM technology the increasing capacity demand could be met and the transport bandwidth costs reduced. However, these solutions do not allocate any networking functionality to the optical layer. To accomplish this feature, optical cross-connects are introduced in the WDM based optical transport networks (OTNs) and an IP-like control plane, based on decentralized processes, decisions and routing entities is suggested (see Fig. 1). This results in an increase of network configuration dynamics, an issue which many standardization bodies and forums are working on, e.g.Automatically Switched Optical Networks (ASON) at the ITU-T.¹ Furthermore, first steps towards practical implementation were done, e.g. in lab experiments² and an interoperability test of so called User Network Interface was performed and demonstrated at Su-perComm 2001.³

© 2002 Optical Society of America