With the daily implementations of FttH networks in urban areas, the materials and processes have significantly improved and we have gained new experience. The difference between the FttH networks and classic networks in the buildings raises a question whether complete optical networks could be an alternative to the classic hybrid copper-optical networks.

We are well aware of that fact. That is why we are continuously seeking, developing and testing new technologies or concepts, which include FttD networks. The FttD solution with star network technology has some significant advantages in terms of security, network management and scalability. Moreover, it is the most favourable in terms of price.

Fttd against CAT / Optical LAN

LAN networks are usually designed with a Ethernet backbone. Every floor has a communication room or rack with one or more switch and patch panels. CAT5 or CAT6 cables are then extended to the end-users. An optical connection between the main communications area and the communications room provides the uplink. The FttD network is designed differently:

• The cost of the optical fibre is relatively small, the density is very high: an optical cable with 96 fibres is almost the same size as the CAT6 cable
   
• Modern fibres are almost the same as copper cables and have a very small loss of efficiency
   
• Splicing and connecting the fibres is increasingly becoming routine work, with sufficient testing and compatible equipment
   
• Optical cables are not limited in terms of distance as are copper cables. Optical fibres are manageable in the normal way with standard optical-electronic equipment.

The topology of the FttD networks is designed as a full star just as with the FttH. The larger distance ensures that communications rooms or racks are no longer needed on every floor, because users can connect directly into the communications area, where they are finalized on the optical panels.

There are two options available in the offices:

1. Each fibre is terminated with an optical connector in a channel, which means that a computer, printers or IP telephones are connected with an optical cable
    
2. Each fibre is terminated with an optical-electronic converter with an RJ45 interface in a channel so that the existing devices can be used with UTP interfaces

The advantages of such topology is a network that derives from one peer and is easier to manage, easier management of capacity, broadband and time lag, easier network design and speed upgrade and there are no communication rooms with air conditioning on each of the floors.