In the era of 5G, edge computing and the cloud, telecommunication networks face increasing demands for high-speed data transfer, seamless connectivity, and cost-effective solutions. The integration of IP and optical networks, along with the concept of disaggregated networks, has emerged as a transformative approach in designing and managing telecommunication transport networks aiming to fulfill these high demands.
What is IP/optical convergence?
Traditionally, IP networks and optical networks were separate entities with distinct functions. IP networks managed packet routing, while optical networks (OTN - optical transport network and WDM – wavelength division multiplexing) facilitated high-speed data transport. IP networks offer flexibility and scalability, ideal for handling variable data traffic. Optical networks, on the other hand, excel in providing high bandwidth and low latency over long distances, making them ideal for data transport. Convergence involves integrating these two networks to achieve resource optimization and operational efficiency. In practice it results in streamlining and simplification of network layers, especially physical layer of OTN/WDM systems (Layer 0) and network layer – IP (Layer 3).
How does IP/optical convergence work?
IP/optical convergence would not be possible without optical network disaggregation. Disaggregating the network involve separating hardware and software components what fosters innovation, network flexibility and cost-effectiveness. This can be achieved by opening the optical network and deploying an open SDN controller that can control and manage a multi-vendor network via open and standard interfaces. Optical transponders can be a typical example of a first open component of a partially disaggregated optical network. They can be delivered by vendors independent to the rest of the optical line system and managed by an SDN controller via industry standard interfaces. Fully disaggregated optical networks will ensure that all components (transponders, ROADMs, Amplifiers) can be delivered by any vendor and managed via standard interfaces. Disaggregation allows operators to select best-of-breed components from different vendors, promoting a competitive supplier ecosystem and reducing vendor lock-in.
IP/optical convergence impact on hardware and software
IP/optical convergence thus can be addressed from the hardware and software perspectives. In the hardware domain, it can be represented by the integration of coherent optics in router platforms through compact coherent pluggable modules compatible with the same form factor as client grey optics, most commonly 100GbE and 400GbE.
In the software domain, IP/optical convergence causes a significant change in system architectures. In order to manage unified networks effectively, operators will require centralized, open, vendor-agnostic, multi-layer SDN controllers providing not only visibility of all involved network layers and domains, but also delivering advanced network applications such as converged path computation engine (PCE), routing optimization and service orchestration. These applications will provide automated provisioning, advanced analytics, and service assurance and optimization.
Challenges and considerations of IP/optical convergence
Implementing IP/optical convergence and disaggregated optical networks presents challenges and considerations, but many operators have already successfully adopted these technologies.
- Interoperability: ensuring seamless integration between different vendors' equipment and software components.
- Security: implementing robust security measures to safeguard the converged network.
- Skills and training: upgrading the workforce's skillset to manage the new converged infrastructure effectively.
The telecommunication industry is witnessing several trends in IP/optical convergence and disaggregated networks, including:
- Greater adoption of SDN technologies to improve network flexibility and efficiency.
- Increased investment in multi-layer protection and restoration solutions for enhanced network resilience.
- Growing collaboration between operators and vendors to develop standardized interfaces for interoperability.
- Exploration of open-source solutions to accelerate innovation and reduce dependency on proprietary systems.
Recent surveys among telecommunication operators highlight the growing interest in IP/optical convergence and disaggregated networks, and the majority of service providers view IP/optical convergence as important or critical for their next-generation networks. Many operators have conducted internal studies to assess the feasibility and benefits of implementing these technologies. IP/optical convergence and disaggregated networks will play a significant role in shaping the future of telecommunication transport networks. As technology continues to evolve, operators will need to embrace these innovations to meet the ever-growing demands of the digital era.