I have been given a grant to make an existing building state of the art by running fiber throughout the space. For this project I will choose an office building as an example of what type of hardware that will be needed inside and outside of the building to accommodate the fiber. I will discuss some safety procedures, and some regulations and standards that will apply to this install that may have not been regarded to when installing copper wire. In this setup, there will be an FTTB (Fiber-to-the-building) passive optical network. On the outside of the building the distribution cables will supply the network access point (NAP) which in turn supplies fiber through drop cables to the buildings NID or Network Interface Device. On the inside of the building in the equipment room will house patch panels and other equipment necessary to support the network.
On the outside of the building fiber can reach the building either via an aerial method which run along existing poles that may already carry electrical power lines or by means of direct burial. These methods may also be used in the event I ever needed to expand our current network to another building in future upgrades. “Cables in aerial installations must be able to withstand loading from high winds, ice, birds and climbing animals, and even windblown debris such as branches.” (Oliviero, 2010) If I choose a direct burial route, one advantage over an aerial installation would be that the fiber is less prone to the weather elements. A disadvantage would be that once the fiber is buried, the cable may be hard to locate if the location is not properly documented due to the fact that fiber cables don’t emit electromagnetic energy the way copper cables do.
On the inside of the building in the equipment room will stand a 19” rack that will house the necessary equipment and help keep the cables organized. For the inside of the building the LAN network will use multimode optical fiber throughout. The horizontal runs will be on horizontal ductwork or conduits depending on what the space calls for. Being that we are running fiber throughout the building instead of copper there are some standards that now apply that may have not applied before. Such as, “Section 4.3 of ANSI/TIA-568-C.3 defines the bend radius requirements for inside plant, indoor-outdoor, outside plant, and drop cables.” (Oliviero, 2010) and “ANSI/TIA-568-C.3 Section 4.3 defines the minimum pull strength requirements for inside plant, indoor-outdoor, outside plant, and drop cables.” (Oliviero, 2010) Understanding these standards with regard to the bend radius and pull load will help ensure we don’t damage the fiber cables during installation. It is also important to use tools that will help with installation such as a pulling eye. A pulling eye will help run cable through walls and conduits. Also it will be helpful if we make sure the conduits that are installed have pull boxes to help ease friction when pulling cables.
Some safety precautions should be followed such as being aware of a cable’s fire resistance and grounding and to follow the standards set forth in Article 770 of the NEC. In this article it will also discuss the installation of fiber optic cables that contain metallic members. When running cable through plenum spaces, it is important to use the specified cable for those specified spaces because plenum cables have a fire resistance and have low smoke producing characteristics. The same goes for installing riser cables. When choosing the proper riser cable it is important that the cable have fire resistant characteristics to avoid spreading fires in such an emergency.
In a situation like this, adding fiber to an already existing infrastructure takes proper planning and insight on what the building currently has and what the ultimate goal is. If a network is currently in use it is important to figure out whether you can going to just upgrade the existing equipment or if you are going to start fresh. Knowing the environment the cables will have to be in is also important. This will help in assisting on where you plan to run the cables, whether it is through plenum spaces, through the walls or along the walls in conduits. If you had to install in a new building, planning may be a little easier because you get to start from scratch and may be able to avoid problems that someone didn’t take into consideration for future upgrades, such as not leaving enough room in conduits to run extra cables. References
Oliviero, A. (2010). WCLS Oliviero/Cabling, 4e. Hoboken, NJ : John Wiley & Sons.