The need for more stable and fast internet increases.

In relatively few years, high speed internet access has become a necessity for most people in daily routines. No matter if you are working from home, watching Netflix from the couch, listening to music from Spotify or gaming online, a stabile and fast connection is needed. For years, WDM technology has been applied in order to achieve this infrastructure, at a reasonable cost and within the physical limitations that we face.

FIBER TO THE HOME

FTTx is normally referred to as:
FTTH (Fiber-to-the-Home)
FTTP (Fiber-to-the-Premise)
FTTC (Fiber-to-the-Curb)
FTTB (Fiber-to-the-Building)

This means that you as a customer, has a fiber connection to either the home/premise, building or the curb.

FTTH and FTTP normally means that the fiber goes inside the house or building. While FTTB means that the fiber stops just outside the building and the connection inside the house is copper. FTTC means that fiber runs to a street cabinet and the rest of the distance is copper.

The main point here is that fibre broadband can mean many things and there is a big difference as a customer between running on a FTTC connection or FTTH/FTTB/FTTP.

FTTx using WDM

FTTx today is commonly build as either Passive Optical Network (PON) or Active Ethernet (P2P) – both approaches apply WDM technology. Most popular solution, especially in the Nordics today, is active ethernet using WDM transceivers, also known as Bidirectional.

Normally a connection between two points, requires a signal going each way which means that one connection requires two individual fiber strands. By applying WDM in a bidirectional transceiver, we can send a signal in both directions in one single strand of fiber.

The main advantage that this brings is the demand of fiber in the ground is cut in half and still allowing each customer to run on a dedicated line.

Moving with the stream

When you make a bidirectional connection, you have two use two types in order make a connection; an A-side and a B-side. This is also referred to as upstream (BX-U) and downstream (BX-D).

The BX-U is traditionally a cheaper laser than the BX-D laser and for that reason it is commonly used in the CPE, in order to keep the cost down for the CPE manufacturer.

Today we see that 1.25Gb/s transceivers is the most common solution, since it enables the ISP to offer any speed from 100Mbit and up to a Gigabit connection, without any change in hardware.

Higher density

In recent years there has been deployed fiber connections to a lot of homes in Europe, especially in the Nordic countries. This is great for the customers but causes an issue for the service providers; space.

Often the node where the customers are connected are placed in tight spaces, like a small installation area in a basement or street cabinet.

With a CSFP you are basically running two bidirectionals in one SFP, which means that you will have two customers per port in your switch. This requires that the switch can support CSFP, but this feature is becoming more common in the market. Not only does this save space, but also the number of switches.

Where are we going

In recent years we have seen a rapid deployment of fiber in the ground all over Europe and this seems to continue. Most networks today can handle speeds up to 1.25Gb/s, but it’s already clear that the private consumer will have even higher needs in the near future. If you take a look at the data consumption in a typical family household today, you will have high quality streaming on several screens during the day, you might have kids gaming online and then we have all our small devices such as smartphones and soon, also home appliances, that will be online.

In order to meet these ever-increasing demands, the next step will be to upgrade the networks to handling speeds up to 10Gb/s. But so far we can only guess what the next step will be.