By Jon Baldry, Infinera
The transition to distributed access architectures (DAA) and particularly Remote-PHY or Remote MAC/PHY is undoubtedly one of the most significant architectural changes to hit the cable world. Whilst this has an enormous impact on the architecture of the last mile as it moves to an N+0 architecture there is a very significant knock-on effect to the DWDM optical network that supports this fiber-deep access network.
Cable MSOs across the globe are evaluating and planning for all aspects of DAA, including revamped DWDM-based optical infrastructure. As part of this evaluation MSOs need to consider some obvious and some less obvious impacts on the optical network, these include:
- Scale – DAA will drive massive bandwidth growth per home and therefore considerably high bandwidth within the aggregation and transport network. What advances in optical technology help drive down cost per bit in high-scale transport?
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Fiber-Deep – Pushing fiber and DWDM deeper into access networks brings additional challenges:
- Host independence – Can DWDM optics deploy directly into 3rd party devices to avoid the need for additional DWDM termination hardware?
- Autotune ability – Can DWDM optics help lower operational cost and rollout bottlenecks by learning their “color” from the network?
- Limited space and power in secondary hubs – Deploying real world networks quite often comes down to available space and power. How can the optical networking infrastructure help address this challenge?
- Advanced CORD architectures – The desire to move to CORD and Spine/Leaf architectures requires any Ethernet aggregation or switching to play a role in a wider Spine/Leaf architecture.
How can this be achieved in modern packet-optical devices? This paper will undertake an assessment of some of the recent trends in the optical networking and how they can be applied to address the considerations and challenges outlined above to help prepare cable MSOs for fiber-deep DAA.