Packet Optical Networking
The core of the network is the workhorse that must handle the enormous amounts of data that are consumed by video, cloud computing and other popular bandwidth-intensive Web 2.0 applications. Yet, most core networks are still too inefficient and limited in bandwidth. Network operators need to rapidly adapt and increase network capacity. They also need to reduce their cost of deploying, operating and scaling optical core networks in order to keep margins strong. With the demand to shorten time-to-revenue and reduce operational expenses, increased network flexibility and lower operational complexity have become important areas of focus for cable operators. Next-generation architectures need to be defined which can cope with these challenges.
A new crucial milestone in optical networking has been reached with the evolution of Dense Wavelength Division Multiplexing (DWDM) technology to support a more flexible and dynamic agile optical core network infrastructure. DWDM networks are now evolving from a virtual fiber infrastructure into a true service provisioning solution.
The speed of data transported over a single wavelength has reached 100Gbit/s and will further scale. At the same time, new modulation schemes provide enhanced optical performance and reach. In combination with a new generation of optical components and devices, this technology simplifies network planning and therefore increases operational efficiency.
Next-generation Reconfigurable Add/Drop Multiplexer (ROADM) technology offers more dynamic and flexible options in operating optical networks. With this technology, new services can be provisioned without performing complex network engineering tasks. The additional integration of OTN and packet switching functionality has seen DWDM technology finally evolve into an intelligent and agile transport solution. The integration of packet-based forwarding and Ethernet service capabilities in particular contribute to the agility of optical transport technology, making multi-layer packet optical technology the ideal choice for innovative network infrastructures.
Figure 1 Multi-layer network architecture
An intelligent control plane starts to play an important role with the evolution of optical networks to a more flexible and dynamic multilayer service provisioning solution. A control plane offers a number of benefits. Control plane enabled agile optical networks support new, dynamic services including bandwidth-on-demand applications and customer-initiated service requests. The control plane also improves network efficiency and resiliency when applied for dynamic service restoration. Finally, the control plane helps to reduce operating expenses by simplifying service turn-up and network maintenance.