Rural Gigabit Boom Expected Thanks to GPON Upgrades

Gigabit network announcements involving Tier 2 and Tier 3 carriers have been coming out more and more frequently – and we may be seeing just the tip of the iceberg.

Adtran, a company that makes a variety of equipment underlying fiber-to-the-home networks, expects to see its equipment deployed in gigabit networks in 50 communities before the end of 2014 and in 150 additional communities in 2015.

“Many of these networks we have already won and we’re just waiting for them to deploy or make the decision to flip the gigabit switch on the existing rollout of gig-ready solutions,” said Kurt Raaflaub, who heads up product marketing for Adtran’s carrier networks division. I talked to him yesterday about gigabit network deployments and he also answered some follow-up questions by email.

A key reason that we’re seeing so much gigabit activity among Tier 2 and Tier 3 telcos is that many of them already have deployed FTTH, which means they’ve already done a large part of the work involved in deploying gigabit service.

I talked to Raaflaub about what’s involved in upgrading these systems to support gigabit service.

Rural Gigabit Broadband Upgrades
Many Tier 2 and Tier 3 FTTH networks are based on GPON technology, with a 2.5 Gbps link from the central office feeding a splitter that serves either 32 or 64 homes. It’s possible to split these systems so that each 2.5 GHz link supports only half the previous number of homes, but as Raaflaub noted, “that starts to be expensive because every time you drop the split count, you have to double the ports.”

Perhaps surprisingly, he expects most carriers to stick with a 32-home count at the splitter – at least for now.

When I asked him how many gigabit homes the 2.5 Gbps link can support, he said the answer depends on average usage per customer. “I could have 50% being gigabit if their usage is low,” he said. “That actually causes less damage than a bunch of 50 meg customers that all have over-the-top video and every evening every family is running a different stream.”

For now take rates are relatively low on gigabit services – and the key to ensuring that those customers who do take gigabit service get good performance is to make sure that the underlying equipment provides advanced traffic management – essentially enabling gigabit customers to get the equivalent of a carpool lane on an expressway, Raaflaub said.

One place where carriers will probably have to increase capacity is in the middle mile, he said. Although some carriers may be “patting themselves on the back” for recently deploying 10 Gbps aggregation networks, Raaflaub said that data rate may quickly become inadequate if the carrier launches gigabit service.

To help ensure that the middle mile doesn’t become a bottleneck, Raaflaub advocates using integrated packet optics supporting DWDM and optical transport networking, thereby enabling existing Sonet circuits to be efficiently carried on optical wavelengths, along with Ethernet traffic.

The Customer Premises Upgrade
When a customer signs on for gigabit service, the carrier typically will have to swap out the optical network terminal at the customer premises, as earlier ONTs typically don’t support gigabit service, Raaflaub said.

The ONT represents the bulk of the overall electronics cost for FTTH, according to Adtran, so getting a gigabit-capable ONT at a reasonable price point is critical to being able to profitably offer gigabit service.

Adtran now offers what it calls a “micro ONT” designed to be installed indoors, potentially simplifying the installation process.

The company has two versions of the product, which was announced yesterday. One version includes a Wi-Fi router and voice gateway and is about the size of a deck of cards, Raaflaub explained.

Another version leaves out the Wi-Fi router and gateway, making it about the size of a large watch and enabling it to sell for less than $100 to the network operator. Raaflaub argued that leaving out this functionality is a good idea because many people don’t need the voice gateway and Wi-Fi technology changes so frequently that customers are better off buying the router as a separate product.

With a sub-$100 price point for the ONT, Raaflaub thinks some service providers will not worry about retrieving it from customers when they move but instead will aim to improve their odds of selling service to the next resident because the equipment will already be there.

It looks like the next 18 months will be an exciting time for gigabit networking, and I’m looking forward to reporting on the new deployments as they are announced.