The widespread adoption of Internet of Things (IoT) and smart home technology has internet service providers (ISPs) and integrators on the hunt for the most effective methods of broadband delivery for many scenarios.

While structured wiring and Wi-Fi installations play a role in broadband delivery, fiber deployment is more than that. Fiber optic internet is delivered to your customers in two main ways: above ground on poles or underground through conduit. In some cases, a combination of the two methods must be used.

Above ground service is the less expensive option of the two as usually the infrastructure is already in place. But aerial cable has its drawbacks. The cable is exposed to the elements and might sag or even break. It’s also at risk of damage from birds, squirrels or traffic incidents. One pole down from a car accident can mean an entire neighborhood loses internet – among other utilities.

Underground deployment

Underground fiber deployment has an increased initial cost, but it’s the preferred method for many municipalities and customers. Buried cable is protected from the elements, which makes it far more reliable. Buried cable is most common for cable that covers a long distance as well.

The terrain and the local conditions need to be taken into account when considering underground broadband deployment. In rocky terrain, cable must be laid in a shallow trench.

The cable will be closer to the surface and more vulnerable to damage. In this case, a more expensive cable that can withstand contact will be required. Cables buried in clay will also need to be of higher quality because the clay can hold stones and push them against the cable. In clay, the trench will also need to be much deeper.

In developed areas, the existing infrastructure can be problematic. Digging through concrete sidewalks and roads is costly and disruptive.

Fiber optic internet is delivered to your customers in two main ways: above ground on poles or underground through conduit. Click To Tweet

Underground methods

There are two main types of underground fiber installation: direct burial and underground duct installation.

With direct burial installation, the cable – typically steel-armored outdoor fiber cable – is either plowed in or trenched. With plowing, the cable is fed into the hole as a specialized vehicle plows the line. With trenching, the trench line is dug by hand or machine and then about six inches of the bottom of it is filled with a granular soil that will protect the cables. The cable is laid in the trench, and then another six inches of protective granular soil is laid on top.

Plowing is faster than trenching, but it should only be done if the soil composition is unlikely to damage the cable.

When underground cable installation uses ducts, a less rugged cable can be used.

Underground duct installations are common in urban areas.

A method that is becoming increasingly popular in urban areas is microtrenching. This involved using a diamond circular saw to cut a 4-inch deep, maximum 1.5-inch wide trench into sidewalks or roads. Microduct is then laid into the trench and hot polymer is poured in to seal the trench.

When tunneling goes wrong

In 2017 a telco in Canada used tunneling to deliver fiber-optic internet to neighborhoods in Toronto. In one area, there were problems. Installers originally thought they’d need a 12-inch wide hole, but in fact, they required a hole large enough for a 33-inch wide box. As a result, one resident lost a tree in their  yard. Microtrenching is a method that can avoid these situations.

One thing is certain, fiber deployment in all its forms will continue. Understanding the options faced by ISPs will help you articulate any landscape changes your customers might face.