In recent times, developing nations of Africa, South East Asia and Latin America are witnessing massive build-outs and/or upgrades in terrestrial optical backbone networks that distribute high-speed Internet access to different parts of these countries. This is driven by the growing deployment of new submarine cables and Internet exchange points (IXPs) that have brought these hitherto unconnected geographies into the mainstream. Rapid adoption of affordable smartphones and mobile broadband services in the developing markets are further catalysing this trend. On the other hand, in the more developed markets, the explosion of packetized voice, high-bandwidth data and video traffic is putting severe capacity and service quality demands on optical backbone networks.
Balancing Costs and Revenues: Service providers building optical backbone networks face a serious challenge in meeting two conflicting business requirements. The optical backbone network has to simultaneously balance the total cost of optical transmission per bit for large traffic volumes with the ability to continuously deliver new services and generate additional revenue streams for realizing maximum profits.
Multilayer Optimization: It is widely known that network traffic should be handled at the lowest OSI layer in order to maximize capex and opex efficiency. However, in traditional optical backbone architectures, a significant percentage of network traffic is processed at the higher IP layers at service routers resulting in sub-optimal implementations that consume a larger number of expensive router ports and client interfaces on the optical transmission equipment. Hence by offloading non-IP service traffic and transit traffic to DWDM wavelengths or OTN circuits that bypass the router layer, significant cost savings are possible.
Efficient Traffic Grooming: In optical backbone networks, it is essential to maximize the utilization of high-capacity 40G/100G/100G+ wavelengths by ensuring that available service traffic is efficiently packed or groomed in provisioned lambdas. Optimization can be achieved at the optical layer (e.g., advanced ROADMs), OTN layer (sub-lambda grooming) or at the packet layer.
Bandwidth Scalability: Optical Backbone networks of today have to carry a wide range and volume of high-bandwidth consumer data services and business applications that are dominated by video traffic. It is therefore necessary for these networks to have the ability to continuously scale to higher speed wavelengths (100G/200G/400G and beyond) with support for multi-terabit switching at OTN/PTN layers.