Fiber Optic Is The Trend In Networks Compared With Copper

Fiber optics is a hot trend in today’s world of communication network, which is a technology that uses glass (or plastic) threads (fibers) to transmit large amount of data. In recent years it has become apparent that fiber-optics are now replacing copper wires as the best means of communication signal transmission. They span the long distances more easily and provide backbones for many communication networks. Why fiber optic is gradually replacing copper networks, we first should konw the pros and cons of copper.

Pros and cons of copper

Telephone companies have long used copper lines, while the cable television companies have relied on coaxial cable for TV, Internet, and VoIP(Voice over Internet Phone) telephone service. Both industries now are making increased use of fiber, hybrid fiber-copper, or hybrid fiber-coaxial cable lines.

The benefit of the old copper service is that, unlike fiber and hybrid-fiber lines, it carries not only the voice and data signals but also the power to operate a standard, non-cordless telephone. The phone company itself provides that power, which often keeps the phones working even when a problem at the power company knocks out electric service.

But traditional copper telephone lines can’t handle the large amount of data required for television and high-speed Internet services, especially over long distances. Although advanced techniques can enhance copper’s capabilities and most other companies are installing fiber or hybrid fiber lines, in some cases alongside the copper ones. We’ve found that telephone and cable company terms and conditions typically warn customers that these systems can’t maintain phone service indefinitely during a power failure, if at all.

The problem is greatest with cable company VoIP services and with systems that use fiber lines all the way to the home. It can be less of a concern with hybrid copper-fiber systems, in which copper lines carry the signal the last mile or so to the home. In those systems, carriers can maintain phone power by installing batteries and generators at the point where the fiber meets the copper.

Why Use Fiber Optic? Is Copper Really Cheaper Than Fiber?

Telcos use fiber to connect all their central offices and long distance switches because it has thousands of times the bandwidth of copper wire and can carry signals hundreds of times further before needing a repeater. The CATV companies use fiber because it give them greater reliability and the opportunity to offer new services, like phone service and Internet connections. Both telcos and CATV operators use fiber for economic reasons, but their cost justification requires adopting new network architectures to take advantage of fiber’s strengths.

When it comes to the cost, fiber optic is always considered to be more expensive than copper cabling. Whatever you look at – cable, fiber termination kit or networking electronics – fiber costs more. So isn’t it obvious that Fiber Optic Network is more expensive than copper? Maybe not! Looking at the cabling component costs may be not a good way to analyze total network costs. A properly designed premises cabling network can also be less expensive.

Fiber optic network has become the protagonist

The most of today’s telecommunication systems is run on a fiber optic network. This has been largely due to the fact that such networks are perfect for transferring information. The development in fiber optics continues to enhance considerably during the last decade, providing more and more benefits to their users.

It does not take a specialist scientist to know just how the process works. An optical fiber can be used to transmit a pulse of light in one spot to another. An electromagnetic carrier wave will be modulated in order to use the light to transfer the data. A transmitter is thus required to create the signal before is distributed across the said cable. It is important to observe that such networks also counteract any distortions to the signal, which would result in interference. When the signal is received at the other end, it’s converted into an electric signal.

Is transmission of data an issue for you together with your old networking technology? Your company should then consider installing a fiber optic network! Light is passed in the form of light pulses with an optical glass fiber. This beats the traditional way of transmitting information with the help of copper wires, because this approach to using optical fiber is quicker and is therefore a more sensible choice.

All this adds to the price of optical fiber being relatively high. Fiber optic networks are mainly suited in situations where information is transmitted to longer distances. Including several telephone companies too. These fiber optic networks can carry higher levels of data in a nutshell distances too.

The rapid growth and development of the internet in recent years has taken about the requirement for new methods to transfer information. Naturally, the faster this process is performed, the better for everyone. However, the amount of virtual traffic making the rounds the world has also been steadily increasing, so these kinds of networks have become indispensable in transferring data wisely.

Telephone companies have played the most significant part within the increasing reliance on fiber optics. Actually, numerous telecommunication companies realised the future is determined by such cables and optical solutions rather than the old copper wires of that time. The possibility of monopolizing the market drove these companies to take a position a lot in fiber optics.

Not only the larger companies use fiber optics but also the smaller business firms and personnel. Instead of using wireless networks this fiber optic technology can be easily be implemented in the home based computer networks too. These optical fibers are generally made from plastic. Anybody who wants a faster connection may use Ethernet technology at home or in the working environment Due to the low power LED bulbs been used, the constant maintenance cost of fiber optic networks are comparatively low.

In the educational sphere, fiber optic networks are also an instantaneous success. One must understand that nowadays education has become increasingly reliant on technology, so computers are playing a chief role in schools. Universities all around the world employ such networks to transfer educational matter between students and lecturers, in addition to between the students themselves.

There isn’t any doubt that these kinds of networks continues to shape the long run in regards to the change in information. More and more governments, companies and educational institutions are purchasing fiber optic infrastructure as it is clear that right now there isn’t any better alternative in the field.

However, fiber optic networks haven’t been implemented up to now in lots of parts of the country. Another major factor for that less using fiber optics is the labour charges involved with installation. The glass fiber is more sensitive than copper wires, which means that more care needs to be taken in installing and maintaining a fiber optic network. For this reason you will find several layers since the glass fiber in fiber optics.

About the author:

Fiberstore is experienced on fiber optic network products. Learn a little more about Cisco SFP and wire stripper on www.FiberStore.com.

What is Reconfigurable Optical Add-Drop Multiplexer

In the fiber optic network which uses wavelength division multiplexing (WDM), reconfigurable optical add-drop multiplexer (ROADM) is used to remotely add, block, pass or redirect modulated light emissions-infrared and visible-within a range of wavelengths.

With ROADM devices, signal switching doesn’t need optical-to-electric and electric-to-optical conversions. Instead, outgoing light beams can be generated, incoming beams could be terminated or beams could be passed through the device unmodified. This is achieved through wavelength-selective switch (WSS) components within the device.

A ROADM allows remote configuration and reconfiguration of emissions; bandwidth could be assigned when needed and without interrupting concurrent traffic, and power balancing is automatic. Most ROADM devices use technologies according to first-generation, wavelength blocking (WB) or second generation, planar light-wave circuit (PLC) technology. Whenever a wavelength change is required inside a specific channel, these technologies filter light emissions, extract data and impress data onto another emission. This method is more streamlined using PLC technology.

The different switching technologies in ROADM devices include microelectronic mirrors, live view screen, thermo-optic and beam-steering switches in planar waveguide circuits, and tunable optical filters.

ROADM devices were initially used in long-haul DWDM equipment. By 2005, metropolitan networks began using ROADMs in reaction to increased interest in Ethernet, as well as high-speed data, audio and video services. Within the ensuing years, ROADM devices have brought bandwidth flexibility and operational efficiency to networks. ROADM-based networks are enabling an automated optical layer with dynamic multipoint connectivity, independent wavelength add-drop, remote bandwidth allocation that has been enhanced power management capabilities.

Combined with the benefits of ROADM comes the inevitable need for fiber optic testing that safeguards function and helps to make sure performance. Here are common testing-related challenges to consider in ROADM-based networks.

1. Increases both in insertion loss per node and insertion loss per channel

2. The need to measure optical loss per channel for multiple ROADM configurations

3. The necessity to measure optical signal-to-noise ratios utilizing a precise and repeatable method

4. The impact of possible bandwidth thinning, other changes to bandwidth, and dispersion, that is of particular concern in multiple cascaded devices and 40 Gbit/s systems

5. Compliance using the optical transport network (OTN) standard-ITU-T G.709 standard

Unlike the optical add-drop multiplexer, Capabilities of ROADM test equipment should encompass optical spectrum analysis (OSA), and OTN performance qualifiers for newly commissioned links, along with the transport layer and all ROADM-supported interfaces. Major manufacturers of OSA and related electronic test equipment include, FiberStore, Anritsu, Digital Lightwave, Exfo and JDSU Test.

Source: http://www.fiberstore.com/

Higher Data Throughput From Multimode Fiber Patch Cables

Information available at our fingertips in form of digital data today has swelled up to levels which had never been before. At the same time, real time communication has exponentially increased to extremely high levels. A whole class of applications have emerged that demand for transmission of high-speed data.

Necessity may be the mother of invention – optical fiber networks have been invented and deployed to solve the problem of high volume data exchange. And multimode fiber patch cables have grown to be the very first choice one of the different connectors of the wired carriers with endpoint devices.

What are the speed-hungry and volume-hungry data centric applications that have created this entire demand? Some examples of those applications are the Internet, the local area multi-computer networks, the phone networks and the ATM networks. There are many more applications with intense hunger for fast communication resources. For those practical purposes, these communication channels need a high-speed network that can carry enormous volumes of data with minimal attenuation and extreme accuracy. The modern fiber optic cable technology provides exactly this sort of communication.

The multimode patch cables are used to connect this data transmitted over the network towards the devices that they target to cater. These patches may also be used to connect the two loose ends of two fiber optic cables. The patch cables have to be multimode when the requirement is to support multimode optical fibers.

What is a multimode cable poor fiber optics? A multimode is one in which multiple packets of data can be simultaneously carried across the wire. The result is that the network can carry numerous data packets at a instant of time. The multimode mainline network cables are usually short long since the target with these cables is to support high speed and high power multiuser systems in a localized sense. The patches are compatible with the network cables to enable the machine remain aligned with the network objectives. Consequently the multimode patches support multiple user applications transferring data simultaneously, as well as retain the qualities of standard single mode patches like the high network speed, low network hindrances and occasional external interferences.

It’s also interesting to note that the end point devices these patch cables connect can be heterogeneous in nature. The aperture the end point device requires and types of applications supported may be diverse. There exist several different kinds of multimode fiber patch cables you can use based upon the requirements. And depending upon the exact reason why you have to install the patch on your fiber optic network, you shall need to select your patch and go ahead with the required installation.

Source: http://www.fiberstore.com/

Several Variable Optical Attenuator Introduction

Variable optical attenuator (VOA) has a wide range of applications in optical communication, and its main function is to reduce or control the optical signal.

The basic characteristics of fiber optic network should be Variable, especially with the application of DWDM transmission systems and EDFA in optical communication, it must be carried out in a plurality of optical signal on the transmission channel gain flattening or equalization, channel power in the optical receiver. The side to be dynamic saturation control, optical networks also need to control for other signals, making the VOA become indispensable key components. In addition, VOA also can be combined with other optical communication components and this pushed itself to the characteristics of the high-level module.

In recent years, there appeared many technologies on manufacture of variable optical attenuator, including mechanical VOA, magneto-optical VOA, LCD VOA, MEMS VOA, thermo-optic VOA and acousto-optic VOA.

Mechanical VOA
The principle is to use a stepper motor drag neutral gradient filter, its output optical power at a predetermined attenuation rule change when the different positions of the light beam passes through the filter, so as to achieve the purpose of adjusting the amount of attenuation. There is also a mechanical polarized optical attenuator. Its basic principle is that the light beam emitted from the ingress port reflected by the reflection sheet to the port, the the reflector coupling efficiency between the two ports by the inclination angle of the reflection sheet to the control, enabling adjustment of the light attenuation. The inclination of the reflection sheet from a variety of different mechanisms to control. Mechanical type optical attenuator is more traditional solutions, so far, the VOA application in the system most used mechanical method to achieve attenuation. The type of optical attenuator with mature technology, optical properties, low insertion loss, polarization dependent loss, without temperature control, etc.; disadvantage is that the larger, more complex structure components, the response rate is not high, it is difficult to automate the production is not conducive to integration.

Magneto-optical VOA
Magneto-optical VOA is the use of some of the substances in the magnetic field is shown by the changes in optical properties, such as magnetic rotation effect (Faraday effect) can also be achieved attenuation of the light energy, so as to achieve the purpose of adjusting the optical signal. The magneto-optical effect of the material and in combination with other techniques, you can create a high performance, small size, high response and the structure is relatively simple optical attenuator. This is LLL device using discrete technology to produce the optical attenuator to be a further development of the field.

LCD VOA
Utilizing a liquid crystal refractive index anisotropy in the liquid crystal VOA shows birefringence. When an external electric field is applied, the orientation of the liquid crystal molecules are rearranged, will result in the change in its transmission characteristics. The type of attenuation can be achieved by light intensity change of the type of voltage control is applied to the two electrodes in the liquid crystal. The liquid crystal optical attenuator VOA can achieve the miniaturization and high response. But at the same time the liquid crystal material into a larger loss, the production process is relatively more complex, in particular, is influenced by environmental factors, its advantage is a low cost, there are commercial batch.

MEMS VOA
MEMS is the technology of the new applications in this area, After several years of development, the MEMS chip production process has become more mature, a strong impetus to the application of the MEMS optical attenuator. Optical network applications, MEMS technology-based products also have the obvious advantage on price and performance. MEMS VOA has been very mature, and mass production and large-scale application. Because of yield problems, in terms of price also facing challenges In addition, micro-electro-mechanical components, reliability is sometimes less than ideal. The early MEMS VOA using laser welding, into a larger device, and the production efficiency is low, and high assembly costs. Currently, the market also introduced a MEMS VOA plastic technology, a good solution to this problem.

Thermo-optic VOA
Thermo-optic VOA mainly using some of the material changes in the optical properties of temperature field characteristics, such as temperature changes caused by the thermo-optical refractive index change. According to the structure of the different, can be divided into two categories, leak-and open-light type VOA. Thermo-optic VOA due to heating, cooling device is relatively complex, a function of the mathematical relationship between the temperature field photoconductive medium refractive index is complex and difficult to accurately quantify and control, especially the longer response time hindered its application in modern optical communication .

Acousto-optic VOA
The basic principle is to use the cyclical strain, resulting in a periodic variation of the refractive index, equal to create a phase grating for the acousto-optical crystal in the generated under the action of ultrasonic waves, and so can be modulated using the raster beam. Some companies have already claimed to have developed the acousto-optical crystal variable attenuator (called the AVOA). It is understood that the acquisition of the acousto-optic crystal material is no problem, but at this stage of the total cost is high, about 4-5.

Conclusion:

Variable optical attenuator is one of important optical devices in the optical communication system. Over the years, it has been stuck at a mechanical level. Because its size is not conducive to integration, it is generally only suitable for single-channel attenuation. With the development of DWDM system, as well as market the flexibility to upgrade reconfigurable optical add-drop multiplexer (ROADM) potentially huge demand, there need more channels and small size variable optical attenuator array, in particular the integrated VOA product. Traditional mechanical methods can not solve these problems. With the development of fiber optic network, VOAs development trends are: low cost, highly integrated, fast response time as well as integration of hybrid with other optical communication devices.

Source: http://www.fiberstore.com/

Optical WDM in Fiber Optic Network

Optical WDM networks are networks that deploy optical wdm fiber links where each fiber link carries multiple wavelength channels.

An exciting Optical Network (AON) is definitely an optical wdm network which supplies end-to-end optical paths by using all optical nodes that allow optical signal in which to stay optical domain without conversion to electrical signal. AONs are often optical circuit-switched networks where circuits are switched by intermediate nodes in the granularity of the wavelength channel. Hence a circuit-switched AON can also be called a wavelength routing network where optical circuits are equal to wavelength channels.

A wavelength routing network includes optical cross-connect (OXC) and optical add-drop multiplexer (OADM) interconnected by WDM fibers. Transmission of information over this optical network is performed using optical circuit-switching connections, referred to as lightpaths. An OXC is definitely an N * N optical switch with N input fibers and N output fibers with every fiber carries wavelengths. The OXC can optically switch all the incoming wavelengths of its input fibers to the outgoing wavelengths of its output fibers. An OADM can terminate the signals on a quantity of wavelengths and inserts new signals in to these wavelengths. The rest of the wavelengths pass through the OADM transparently.

For a user to deliver data to some destination user, a circuit-switching connection is made by using a wavelength on each hop along the connection path. This unidirectional optical path is known as lightpath and also the node in between each hop is either an OXC or an OADM. These units are utilized within the 100G DWDM networks. A separate lightpath has to be established using different fibers to setup transmission within the opposite direction. To fulfill the wavelength continuity constraint, the same wavelength can be used on every hop along the lightpath. If a lightpath is blocked since the required wavelength is unavailable, a converter in an OXC can transform the optical signal transmitted in one wavelength to another wavelength.

Because the bandwidth of a wavelength is usually much larger than that requires by a single client, traffic glooming is used to allow the bandwidth of the lightpath to be shared by many people clients. The bandwidth of the lightpath is split into subrate units; clients can request one or more subrate units to carry traffic streams at lower rates. For instance, information is transmitted over an optical network using SONET (Synchronous Optical Network) framing with a transmission rate of OC-48 (2.488 Gbps). A lightpath is established from OXC1 to OXC3 through OXC2 using wavelength w, the subrate unit available on this lightpath is OC-3 (155 Mbps). A user on OXC1 can request any integer number of OC-3 subrate units up to a total of 16 to transmit data to another user on OXC3. A network operator can use traffic-groomed lightpaths to provide subrate transport services to the users with the addition of an online network towards the fiber optic network.

Information on a lightpath is typically transmitted using SONET framing. In the future, the data transmitted over optical network uses the brand new ITU-T G.709 standard, referred to as digital wrapper. In ITU-T, an optical network is referred to as the optical transport network (OTN). Listed here are some of the options that come with G.709 standard: 1) The conventional permits transmission of various kinds of traffic: IP packets and gigabit Ethernet frames using Generic Framing Procedure (GFP), ATM cells and SONET/SDH synchronous data. 2) It supports three bit rate granularities: 2.488 Gbps, 9.95 Gbps and 39.81 Gbps. 3) It offers capabilities to monitor an association on an end-to-end basis over several carriers, in addition to over a single carrier. 4) G.709 uses Forward Error Correction (FEC) to detect and correct bit errors brought on by physical impairments in the transmission links.

Lightpath may either be static or dynamic. Static lightpaths are in place using network management procedures and may remain up for a long time. Virtual Private Networks (VPN) could be set up using static lightpaths. Dynamic lightpaths are established instantly using signaling protocols, such as GMPLS (Generalized Multi-Protocol Label Switching) and UNI (User Network Interface) proposed by OIF (Optical Internetworking Forum). GMPLS is definitely an extension of MPLS and is built to apply MPLS label switching techniques to Time Division Multiplexing (TDM) networks and wavelength routing networks, in addition to packet switching networks. The OIF UNI specifies signaling procedures for clients to automatically create, delete and query an association over wavelength routing network. The UNI signaling is implemented by extending the label distribution protocols, LDP and RSVP-TE.