Solutions for the deployment of FTTB networks: which difference between FTTB and FTTH?
Based on a mix of technologies, FTTB (Fibre to the Building) network architectures consists of replacing copper pairs with fibre connectivity solutions , from the PoP (Point of Presence) or FCP (Fibre Concentration Point) all the way to the vicinity of the MDU or the SDU to be connected. The fibre rollout is performed as close as possible to the subscribers without however reaching the premises. For the last mile, technologies such as xDSL or DOCSIS are used in order to reduce at most CAPEX and OPEX.
Which benefits for a HFC connection?
Based on Hybrid Fibre Coaxial connectivity solutions, Fibre to the Basement (FTTB) networks allow:
• A quicker access to very high-speed networks.
Indeed, in the case of a FTTB infrastructure the last mile consists of non-fibre cabling solutions used over short distances and available immediately. This saves telecom field engineers and installers a considerable amount of time as they do not have to install indoor cables, closures or optical telecommunications outlets as in the case of FTTH.
• Simple and fast network management and maintenance. In the event of a network failure, there is no need to make an appointment with the subscriber: the technician does not need to access the subscriber's home/office as he can restore the network by intervening at the opto-electrical node located at the building’s entry.
• Scalability. When there is a need to extend a network, telecom operators can, at any time, increase the bandwidth, speed or the latency performances of their FTTB network by extending the fibre optic rollout over the last mile so to reach the subscriber. To develop FTTB networks into FTTH network, telecom installers can extend the infrastructure by adding a Building Entry Point the ground floor or basement level. An outdoor FO distribution cable will be connected inside the BEP to a riser cable ; This last one will enable the connection to ultrafast broadband networks to subscribers via Floor Distribution Points and indoor fibre drop cables.
• Use environmental friendly connectivity solutions: just as the FTTH, the rollout of FTTB infrastructures can reduce greenhouse gas emissions up to 88% compared to other access technologies.
Ensure reliable networks from the Point of Presence to the Building Entry Optical Distribution Point
To secure reliable and highly performant telecom networks it is fundamental to pay a particular attention to the connectivity solutions used for deploying the FTTB infrastructures. The quality, scalability and security of the network are all criteria to consider when selecting the passive equipment to install. For example, starting from a splitter node and depending on the density of the architecture (low or high density), two network installation configurations are possible:
FTTB deployment – Overhead network installation
An aerial optical cable such as LX030PU can make the junction between an Outdoor Optical Distribution Point size 2 (preconnectorised or for fusion splicing) and an Outdoor Optical Distribution Point size 1 wall-mounted on the building to be connected. The FTTB network will be then extended up to the subscriber’s home or business premises via a copper or coax cable that is already in place. .
Benefits of this configuration:
• Increased network security despite an apparent installation. Indeed, the Eline® Outdoor Optical Distribution Points are designed with a reinforced security system consisting of toggle locks plus triangle key or double lock with triangle key for the pre-connected version.
• An optimised optical power budget throughout the entire FTTB network; thanks to high-end connectivity solutions, telecom operators can guarantee the best speeds to their subscribers.
FTTB deployment – Underground network installation
An underground optical cable such as LM4 and factory pre-terminated can be plugged to an Outdoor Optical Distribution Point installed into a telecom manhole. Thanks to swelling yarns included into its structure this FO outdoor cable can guarantee a reliable transmission of the optical signal even if the telecom manhole is flooded. The LM4 cable is designed for rollouts over network segments of up to 70 meters. The LM4 will be then used for the opto-electrical transition performed by field engineers or installers at the entry of the building to be connected.
Benefits of this configuration:
Versatile solution, the LM4 drop cable fits both for an outdoor and indoor installation, in underground or overhead/façade layout. Thanks to its double sheath construction this cable is a scalable solution allowing to meet eventual network evolutions and upgrade FTTB into FTTH infrastructures. Indeed, the outer sheath of the LM4 can be removed within a couple of seconds so to give access to an indoor drop cable.
