50G Passive Optical Networks (50G-PON): What Is It All About

Subscribers in today's digital age are demanding more. 50-Gigabit-capable passive optical networks (50G-PON) provide the next generation of fiber-to-the-premises (FTTx) deployment capabilities. From entertainment to business applications, subscribers may take advantage of new capabilities well beyond today's XGS-PON-based services.

Defined and adopted by the International Telecommunication Union (ITU), 50G-PON provides seamless integration into existing optical distribution network (ODN) deployments, allowing broadband service providers (BSPs) to deploy GPON and/or XGS-PON and deliver superior services to meet subscriber demands.

What Is New With 50G?

An exciting facet of 50G-PON is the dual rate capability, which allows both asymmetric (50G downstream /25G upstream) and symmetric (50G downstream/50G upstream) 50G-PON to coexist on the ODN simultaneously. This is significant because operators can deploy technology-optimized ONTs for 50G/25G and 50G/50G subscribers targeted to specific residential and business market segments while serving them over the same ODN.

Traditionally, operators could limit services to segment tiers on new technologies leveraging the same next-generation chipsets. In the 50G-PON example, technology-optimized ONTs can serve specific market segments, allowing operators to deploy the optimized ONT technology to ensure higher economic flexibility. This capability also allows BSPs to begin with optimized ONTs for asymmetric services and grow into symmetric service delivery based on market needs.

Four PON Standard Trends

New technology development and improvements are constant endeavors-and passive optical networking standards are no exception. Looking at the evolution of PON standards-from GPON to XGS-PON, and now 50G-PON-we can identify a few trends.

1. New standards and capabilities are introduced every nine to 10 years. The first GPON deployment was in 2007, followed by the first XGS-PON deployment in 2016. We expect the first 50G deployments to begin in 2025-2026.
   
   
2. New technology can take up to 10 years to surpass the previous deployment. Omdia research estimates that XGS-PON ONT sales will surpass global GPON sales in 2027.
   
   
3. Sales of new OLT technology take four years to surpass those of previous OLT technology. Omdia research identified that XGS OLT port sales surpassed GPON OLT port sales in 2021.
   
   
4. The new technology increases performance at least fourfold over the previous generation. GPON, XGS-PON, and 50G follow this 4X or more rule. This guideline ensures technology is sustainable in the market, allowing FTTx-based BSPs to recover and maximize their network investments.

Watch this videoto see how Brightspeed is seamlessly deploying 50G PON next-generation services with Calix.