**5. Usable connectors for glass fibers and polymeric fibers in the home**

The optical polymer fiber POF has particularly good and simple properties for the connection technology between fibers and optical transmitters and receivers [47]. Due to its simple structure, which with a core of 0.98 mm and a cladding of 0.2 mm corresponds exactly to 1 mm outer diameter, the cable can be cut straight with a cutter knife (see illustration) very easily. In contrast to fiber optic connections, the separation and cutting of a plastic fiber is much easier because the fiber optics require very complex mechanics and the dismantling of the fiber optic cables (see YouTube video [48]). A connection of two fibers has particularly low losses, since the large diameter reduces the mechanical boundary conditions for the accuracy of the alignment to + −0.1 mm. This corresponds to a 100 times lower necessary accuracy compared to a fiber optic connector. Because the alignment accuracy between the fiber and the optical element can be measured very generously without generating large losses, the plug-in connections are correspondingly easy to assemble. The **Figure 12** shows an overview of the typical plug connections for POF cables.

A distinction is made between metallic and plastic plugs. The metallic plugs are used in the area of rough environments like car entertainment busses or factory environments for stable connections. The plastic plugs were used in the area of in-house networks without large load peaks.

No plugs are typically used for use in the home, while the fibers can be simply cut off (see **Figure 14**) and butt-inserted into the receptacle of a media converter. This saves a lot of costs and unnecessary time for the connector assembly, as well

**Figure 12.** *Typical plugs for POF connections.*

as a simple possibility for the non-specialist to lay network cables himself without special knowledge. Typical connectors for butt-inserted connections are shown in **Figure 15**.

Another area for the introduction of POF network technology is the construction and connection technology, e.g. of splicing for POF. This would make it possible to directly couple POF without additional components. This technology is established in fiber optic technology, but in a technology that cannot be used for POF. That is why it would be of crucial importance for the cable laying technology of POF to have such a connection technology with innovative approaches. A splice kit (**Figure 13**) has been implemented at the HarzOptics GmbH Company with industrial partners using injection molding technology, which provides very good conditions for an easy-to-use splice [49]. Very low attenuation of 0.2 dB is typical for this spice method. The basic idea is that the fibers are fit very exact into the splice core of 0.98 mm and the core hoe was filled before with glue. The refractive index of the glue is 1,5 and the hardening of the glue is realized by the use of a UV light lamp, which took only 3 minutes to be hardened (**Figure 15**).

**Figure 13.** *Optical splice with low attenuation.*

**Figure 14.** *POF fiber cutting easy with cutter knife.*

#### **Figure 15.**

*POF media convertors, Ethernet switches and 4-port optical POF switch RJ-45 wall outlets with WiFi-Accesspoint (Rutenbeck GmbH).*

For the home sector, also known as domotics, an increasing demand for bandwidth is to be expected over the next few years. One reason for this development is the triple play promoted by the leading telecommunications companies, which means a bundled range of services such as IP telephony, IP TV and the Internet (**Figure 16**). Another term used in this context is the "active house". The development of this concept represents the integration of communication and entertainment, as well as the active control of all functional processes in the house (control of the heating, blinds, monitoring systems, etc.), also known as building automation.

For these areas, active components on the one hand, e.g., media converters for setting up dynamic network structures, and on the other hand, passive optical components such as splitters for the inexpensive construction of such networks are available in sufficient numbers for Ethernet applications up to 1000 Mb/s. There are a variety of applications and simple installation techniques for POF media converters or POF adapters (**Figure 15**) and POF Ethernet switches for installation in flush-mounted switch boxes are available for setting up home networks with polymer fibers [50]. On the user side, one or more ports with RJ-45 interfaces (10/100/1000Base-Tx) are available for connecting the end devices. The polymer fiber is connected on the installation side. The POF is connected to the optical interfaces (1000Base-Fx) using plug-in terminals.

The switch shown also allows the construction of star, bus, tree and ring structures with polymer fiber cables. Some of the ports of POF Ethernet switches even offer Power over Ethernet (PoE) functionality, so that IP telephones, IP cameras or WLAN access points with IEEE 802.11n data rates (up to 240 Mb/s net data rate [51]) can be operated on the POF network without plug-in power supplies.

### **6. Example of an in-house network with optical POF fibers**

A typical example of an application in a single-family home is shown in **Figure 16**. The data which is supplied from outside from the so-called network level 3 via fiber optics or DSL to the house is sent to a router at the house transfer point.

From this router, optical POF fiber cables are installed in all rooms in the house with active switches with four ports and connected there. Forwarding via additional switches the data can easily be routed to each room and connected. Furthermore, a corresponding WiFi module can be integrated in these switches, which can illuminate each room individually with small radio energy and is available for mobile devices in this room. By reducing the radio energy, each room can be connected to its own WiFi radio network and thus does not interfere with the transmission quality of the adjoining rooms. The radio energy must be set so low that the radio waves from the individual WiFi areas in the room do not get into the neighboring room and are attenuated enough by the walls.

It is also possible to lay the polymer fiber slightly behind baseboards in existing structures and thus not have to finance complex and expensive construction measures.

#### **7. Conclusions**

Optical fiber networks are currently the standard for delivering high bandwidth to customers. It was discussed, that there are various access technologies to local networks with a very high bandwidth up to access individual customers in their homes or flats. The use of optical glass fibers or/and polymeric optical fibers in different network topologies in connection to high speed actual WiFi- technologies have been discussed.

Both, the copper networks with CAT connections, as well as the networking with optical glass fiber and optical were compared and their strengths and weaknesses were shown. The Polymer Optical Fiber exhibits many advantages in comparison to glass fiber and copper as the medium for communication. The mentioned applications show different special sectors to the application of one of the three transmission technologies.

The focus in this work lies on the possibility of conveying high data rates, as well as the simplest possible relocation of network components in the SoHo area. In the

#### *Optical Inhouse Networks DOI: http://dx.doi.org/10.5772/intechopen.98921*

area of permanently installed network components, the use of POF fibers proved to be particularly suitable for network bandwidths of up to 1 Gb/s. In addition to the almost relocated optical components, the installation of a wireless network via WiFi is a particularly good addition to make mobile devices easily networkable for the customer. Thus, a recommendation can be issued for both, optical polymer fibers with Ethernet network technology in combination with current WiFi technology. Both system components will experience further expansion stages in the range in the next few years and thus always remain applicable and expandable.
