From CATV to FTTH: Technetix evolving networks since 1990 

Cable television
Cable TV has been around since the 1930s, developed initially as a response to problems associated with traditional over-air transmissions. Factors like transmitter distance and topographical variations meant that broadcasting didn’t reach all homes. Despite televisions costing less and increasing in availability, installing additional transmitters to cover a small percentage of the population wasn’t financially viable; yet this unserved population also wanted to experience the exciting new technology of television.

The solution was surprisingly easy. Large receiving aerials could capture, amplify and distribute the broadcast signal into homes through a network of cables – essentially a larger, more powerful version of what aerial and coaxial cables do in the home.

Diagram of cable TV (CATV)
Cable TV (CATV)

Unaffected by weather and atmospheric conditions, and following a change to the law in 1984 that permitted cable to carry more channels than over-air broadcasting, the advantages of CATV over broadcast TV were quickly realized. CATV’s popularity increased but to support the additional bandwidth required for the additional channels, new hardware was needed to facilitate roll out. With their reputation for problem-solving established, Technetix designed and built the hardware that underpins the CATV network as it exists today. From the core hardware in the roadside cabinets, mid-span amplifiers, taps, and in-home splitters, Technetix have constantly evolved the technology to support more channels and the addition of internet services and video on-demand.

The evolution of broadband
As CATV evolved to support increasing network demand, other methods of delivering internet to the home have too: from the old dial-up modems to today’s fiber-to-the-home (FTTH) connectivity able to provide speeds of up to 1 Gbps. This speed level quickly became a goal for the UK, and the government pledge promised to connect 85% of UK homes to gigabit internet by 2025. Taking advantage of government funding and billions in private equity, a number of smaller ‘Alt-Nets’ (alternative Networks) joined BT and Virgin Media in the race promising to connect millions of homes to full fiber between them.

Swiss Cheese
With the full fiber industry unregulated, the frenzy to claim the lion’s share of customers became something of a wild west. Driven by private equity, the Alt-Nets concentrated on large urban areas: after all, 100,000 homes in a large town is more cost-effective than 500 in a small village. Indiscriminate installation saw operators overbuilding each other’s networks in towns and cities to the detriment of smaller villages and rural areas. Today, the UK is at 68% full fiber coverage; however, the majority of this, covers only densely populated urban areas and larger rural towns.

With fiber’s lifespan expected to last up to 50 years, recouping initial investment looked to be spread over decades and not the typical 5 to 10 years preferred by private equity firms and venture capitalists. If the cost to connect a home to fiber exceeds the potential revenue over the committed investment period, the home is taken out of scope, creating a ‘Swiss Cheese’ effect with the holes representing rural areas without full fiber.

With full fiber facilitating most urban areas, investors with longer-term strategies are now concentrating on these rural areas, since the potential for competitor overbuild is lower. However, unless a more cost-effective method of deployment to these homes can be found, many of them – especially in ultra rural locations – are unlikely to be included in build plans.

The rOLT (Remote Optical Line Terminal)
An OLT has a maximum useable distance to the optical network unit (ONU) in the home. This is due to losses from splits, splices and connectors along the length of the fiber. With current technology, the maximum distance is around 15km. However, a point-to-point connection down a single fiber can easily travel 50km or more.  Getting the required backhaul bandwidth to a location is relatively straightforward,  but the costs associated with a traditional FTTH build are prohibitively high.

The Technetix rOLT (Remote Optical Line Terminal) has been designed to serve a small (max 512) number of homes from an IP68-rated hardened enclosure which can be deployed in the center of the required network area rather than miles away in a roadside cabinet.

Banner image of ROLT
Remote OLT

The rOLT does not require a cabinet, the installation of which can be upwards of £60k in rural environments. It uses 48 V DC power, draws only 50 W at full load, and requires no cooling. It can even be powered using solar and wind or draw power from a CATV network.

The rOLT consists of a power supply and one or two carrier grade switches. In a single switch configuration, the system can support two Micro OLT modules and two 10 Gbps backhaul modules, providing up to 20 Gbps backhaul, and support up to 256 homes. With a two-switch configuration, these numbers are doubled. This represents enough capacity to fill the majority of ‘Swiss cheese’ holes left by the traditional FTTH infrastructure.

Other uses and advantages of rOLT


The active hardware, usually housed in the hardened enclosure, can also be rack mounted creating ideal solution for MDU deployments. Furthermore, options to mount it on the side of community buildings above head height or on a telegraph pole offers a more localized installation option and reduces susceptibility to damage or community objection. If required, configuration as a pair presents resilience in the event of unsustainable battery draw during the likes of an extended power failure. In these instances, a fraction of customers would be affected compared to the impact of taking a roadside cabinet offline.

Distributed Architecture

Traditionally FTTH infrastructure relies on large roadside cabinets or strategically located micro-exchanges which can service in excess of 6,000 homes when fully populated. However, they have significant disadvantages:

Image of FTTH infrastructure
Image of roadside cabinets
  1. Power consumption – up to 7.2Kw
  2. Damage risks (accidental from RTAs or deliberate criminal damage) affect large numbers of customers
  3. Resistance from local residents, especially in small towns and villages
  4. Planning permission required for micro exchanges

In summary, Technetix began its journey with CATV distribution hardware, ensuring that those on the edge of the network had access to quality service. Today, we continue to apply this principle for FTTP with our highly innovative rOLT.

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Author – Glenn Dunwell, Technical Sales Consultant
Glenn is a seasoned Telecommunications professional with over 25 years in the telecoms industry. He is a Fellow of the Institute of Telecommunications professionals and is employed at Technetix as a Technical Sales Consultant. For more information on our FTTx product range please reach out through our contact page.

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