Generally, sooner or later any network installer and planner reaches the limits of current network media – be it coaxial cables using HFC technology or EOC, or copper networks using ADSL or VDSL, or even Ethernet over Power networks. And yes, radio waves also have it’s limits as we will see further in this article. In general, here are 10 main advantages to chose optical fiber as transmission media for your networks:
- Long transmission distance
- Dielectric protection and construction
- Small size
- Light weight
- Relatively easy installation (but skills are needed though)
- Secure transmission (as oposed to wireless especially)
- EMI and RFI immunity (you have no distortions for example in CCTV signal)
- Low cost
- Unlimited Bandwidth
- Not attractive to fraud
Optical Fiber really have almost no limits how fast and much information can be sent through it. There is a study from Lucent Technologies, what theoretically single mode fiber is capable to transmit on even 200 Tbps speed!
Now isn’t that “enough” can you think application that will use that amount of speed? At least fore FTTH applications we here in AD-net focus, that is not even near future.
Why is that so, that fiber optical cables are able to carry such a speeds? This is because technology allows to use modulators on very high datarates. Just check this 40 GB fiber media converter – isn’t that so long ago when having gigabit connection was such a non-achievable dream even in highly urbanized areas?
Second thing worth to remember is that over fiber optical cable you are able to transmit several wavelengths at the same time, thus doubling, or multiplying speed many times. For example first these examples in market was classic WDM single fiber media converters, which used 2 wavelengths – 1310 and 1550 nm over same 1 fiber, and later CWDM – Coarse Wavelength Division Multiplexing, and DWDM – Dense Wavelenght Division Multiplexing were introduced.
Just check here, how dense now DWDM signals are populated at same fiber!
CWDM then already as opposite to WDM with it’s 1310/1550 nm division already used up to 16 channels (or wavelenghts), while DWDM already allows send up to 200 of wavelenghts, over same fiber!
So, when we say unlimited bandwidth, we mean that what you can is to install a fiber, and then always come back upgrading to to higher speed as market needs are becoming more and more hungry, people rely more and more on streaming video services instead of downloading content before watching it. This is another benefit of fiber optical equipment itself, because all components made usually supports vendor interoperability, and you can replace even parts of the elements only.
Long Transmission Distance
If you are limited with 100 m or so of UTP Cat 5 cable for your Ethernet, then even wiring a building is a problem not talking about last mile access. This is why nowadays, ADSL last mile access is widely replaced by FTTx PON based solutions.
It is not that expensive any more to send gigabit ethernet over 120 km and more and even using 1 fiber only. That is not possible using copper media and hard to be done by means of wireless.
EMI and RFI immunity
These 2 benefits are mainly because low attenuation rate of optical signal and low pulse dispersion. So, such an immunity just dramatically increases hassles and you can pull optical strand just near some power wiring in building. Remember the days when you installed CCTV security system for a bank and then to see later distorted signal at DVR signal? Well these days are over, because now you can send video direct over the fiber. Now matter, be it HDMI, CCTV PAL type, or DVI or even KVM for the computer, all is possible.
So, add it all together now – high transmission distances, resistance and immunity to noise, and hey – fraudsters will not steal it, since it’s not valuable as copper – we have a total project costs spiraling down. Now even countries in for example middle east who preferred quick and easy installation of radio links, now prefer invest in optical fiber, because spectrum get’s crowded, cables stolen, and signal degrades on bad weather – you name it! That adds not just to cable costs, but also increases maintenance cost and requires keep more personnel.
This is why fiber and only fiber now is a main choice for FTTx networks.
Now, remember that last thunderstorm that killed 40% of your EoC based coaxial network modems, and oh my – even burned network cards of some enduser PC’s? That day your technical support guys wanted leave, right?
So, yes, no any specific grounding (as for cable itself) will be needed.
And sometimes, building electric current can get injected in regular copper communication cables, and that can cause injuries and death of people. Which ISP want’s these troubles?
For copper cables it just meant this. More channels bigger size. More strands, more cross interference. Before, when between cities these cables were installed as backbones, you could here someone else talking in your conversation on phone. And what you do when you have digged in a cable and you run out of the capacity? With fiber, you can only change equipment or even a fiber module to higher speed, but here you need this huge investment of laying completely new cable.
And this is not just digging – you need apply permissions from authorities to dig streets – that is another nightmare usually.
So, if that copper cable is big and fat, it must be heave as well, right? And the more heavy it is, more copper in there, the more risks are that someone will steal a part of it for precious copper needs. This allows fiber to be used even in temporary applications, like concerts to connect large screens using HDMI over fiber converter, disaster affected areas and more. And then consider ships and aircrafts – for these, any additional weight is a concern.
Yes, this is a bit arguable topic, since if copper cable relatively “green” technician without any special tools will somehow finally crimp it on, and get at least some communication on, then here some training will be needed. BUT, after it’s done, it’s a easy process.
First of all, it is clear that security risks comes from 2 sources – signal is getting radiated beyong cable and there is a possibilities easily tap in as parallel channel.
How to do that with copper it is easily under stable for anyone, and also it is clear that modulated signal over copper cables can be received by sensitive equipment.
For optical cable, signal is traveling in the center of cable (core), and so it is not radiated outside of the cable at all. Also, if you try tap in the cable, it will degrade the optical signal and monitoring personnel will see that immediately and use reflectometer to find exact place where it happened.
Not attractive to fraud
Some countries sometimes have this all the time. After all copper and any other metal is a money, and asset whatsoever. So, if that is copper and robbers know that, you can wake up one morning with several km span of cable cut out. They won’t do that fiber small size optical cable.