Fiber and the Art of Next-Generation PON

Fiber is the bedrock of modern telecommunications technology that underpins the industry’s spectacular growth. It plays a crucial role in connecting people, businesses, and smart cities. Fiber networks have virtually unlimited bandwidth potential, and every new generation of passive optical network (PON) technology unlocks more of that potential by running faster on new wavelengths (or colors of light).

Today, most fiber access networks use GPON technology to deliver speeds of 1 Gbps. There are >300 gigabit networks worldwide, many of them in the U.S. By adding a new wavelength with XGS-PON technology, operators can add 10X capacity to their existing fiber network.

The need for speed is driven by more bandwidth-hungry applications, more users, and more devices per home. But speed is not the only driver. The “big pipe” of XGS-PON allows operators to converge more services on the same fiber infrastructure, create more revenues, and accelerate network monetization.

Enter XGS-PON: the game changer

XGS-PON is well placed to address the bandwidth requirements for both consumers and businesses. It is forecasted that XGS-PON will overtake GPON shipments in as little as two years and become the mainstream PON technology. Now that evolution truly is a game changer for numerous reasons:

XGS-PON delivers unbeatable symmetrical speeds (in upstream and downstream) suitable for business connectivity and premium user experiences.
It creates significant savings and revenues by converging business, consumer, and 5G transport services on a single network.
It attracts new investment in fiber; alternative operators, tower companies, investors, etc., have been quick to recognize this as a market-disrupting opportunity.
It allows regional communication services providers (CSPs) to protect their market from bigger players. By seamlessly jumping onto XGS-PON, they can provide an ultra-fast and reliable network to their customers, while making their market less attractive for competition.
It lets multiple system operators (MSOs) complement their cable deployments and compete with CSPs.
XGS-PON is easy and cost-effective to upgrade on an existing PON infrastructure and supports symmetrical bit rates.

Given the ability to overlay XGS-PON over the existing GPON network, the return on investment is accelerated, with the payback period reduced by at least 20%. And XGS-PON enables opportunities for additional revenues. Besides adding wholesale, business, and mobile transport revenues, operators should consider tactics to increase revenues in the consumer segment. Consumers are often willing to pay a premium price for a premium service, as witnessed in many real-world networks. High-capacity and low-latency XGS-PON offers opportunities to monetize a variety of special-service packages such as “gamer broadband packages,” “working from home packages,” “edge computing” for medical and financial branch offices, etc.

So, what should your PON migration strategy be?

Given the rapid evolution in technology and consumer requirements, it is imperative to implement a plan that is future proof. Let’s explore a few options based on the type of your existing network infrastructure:

Greenfield deployments: In deployments where fiber is being newly laid, starting with XGS-PON makes the most sense. Given that laying fiber (installing cables, ducts, etc.) takes the lion’s share of costs and needs to be done anyways, the cost delta between GPON and XGS-PON deployment is very low.

Upgrade strategy in brownfield deployments: For those with existing fiber networks, there are new techniques available that enable a seamless evolution. The multi-PON approach, also called a combo approach, has recently gained a lot of traction. It combines GPON, XGS-PON, and a co-existence element on the same PON port in the access node. So not only can you easily upgrade your network but also enjoy a smaller cabling, equipment, and migration effort. In other words, your GPON network is actually 10G ready from day 1, and when needed, XGS-PON can be activated remotely.

XGS-PON gets even better with 25G

To maximize the benefits of XGS-PON, some vendors now enable three generations of PON technologies (GPON, XGS-PON & 25G PON) to be implemented on a single piece of hardware. This means that all operators who deploy such optical line terminals (OLTs) today automatically have 25-Gbps capabilities in their network. In addition, such OLTs support the capabilities needed in future fiber networks - low latency for 5G transport and 50% less power consumption than previous generations.

The significant advantages of such multi PON OLTs have been established by the fact that they have been adopted by nine out of ten top CSPs in the U.S. Meanwhile, many Tier 2/3 CSPs and utilities, including Frontier, Hotwire, TDS, EPB, and Shentel, have also signed up for it.

Future infrastructure now

There is no stopping with fiber. Higher-speed 25-Gbps PON is available today and was proven in a live network. Standardization work on a 50 Gbps network is also underway, and earlier this year the industry saw the first to demo 100-Gbps speeds on a PON. While 50G and 100G PON are still a long way from commercially availability, 25G PON is here now. But with XGS-PON largely capable to handle current demand, is there really any need for a next next-generation PON?

The short answer is yes, because the possibility of easily increasing capacity creates new opportunities for broadband providers. CSPs see the need for >10 Gbps for enterprises, for dense 5G transport, and for more efficient delivery of multi-gigabit speeds in dense areas.

And 25G PON is the simplest way to supercharge your XGS-PON. It is available on the same hardware deployed today for XGS-PON and can co-exist with GPON and XGS-PON. It’s not a new upgrade cycle, or a disruptive technology, but an incredibly simple way to future-proof your XGS-PON deployment.

Ana Pesovic is marketing director, Fixed Networks, at Nokia. She has more than 20 years of experience in fiber access technologies.