FTTH Business Guide - AWT.be

Outside plant
The horizontal portion of the outside plant (OSP) brings the fibre down the street,
passing all the homes or buildings. In most cases the OSP has the largest influence
on cost, especially if the cables need to be put in the ground.
Although there is always a fibre between the central hub and the customers, the
way that this is routed will have a major impact on construction cost. The
possibility to reuse existing ducts and conduits should always be considered. If
ducts are already in place for part of the route, then blowing fibre through them
could substantially reduce the deployment cost over that length.
The lowest cost solution where there is no existing build is an aerial route, where
power (or similar) poles are used to string the fibre between. This clearly plays
into the hands of any utility companies that want to be part of a fibre based
business. A similar approach that may be used is stapling. Here the fibre is
literally passed around the outside of the building and stapled in place.
Where the above is not possible, the fibre will need to be dug. This can be done
using a shallow digging approach called micro-trenching (at about twice the price
per metre of aerial) or a deeper, full trench method (roughly doubling the price
again at least).
The state of the existing pavements will impact these costs for digging. Where
ornate paving is in place then the cost to make good the pavement will be greatly
increased. Even the particular nature of the subsoil has an impact on costs: soft
ground may permit fast construction using dedicated mole equipment: detailed
local knowledge is invaluable.
The cost for rights-of-way should also be taken in to consideration when choosing
the route of the network. These costs consist of annual fees and costs to get
permissions.
Whatever the method of building fibre around a town or city, the average length
of fibre per home passed will have a serious impact on the financing. Individual
homes will clearly be the highest cost to connect whilst large apartment blocks will
be the cheapest.
Of course, demographics cannot be changed, but they should be taken into
consideration when deciding where to roll out the network and which areas to
target first.
Aiming to pass as many homes as possible as quickly as possible is an
uneconomical way of rolling out a network. Your business case would normally
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