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Actually, the speed of light in fibre optics is only 2/3 that of radio waves in air or a vacuum

Actually no...

What causes the delay (which looks like a lowered velocity of light but isn't) in a fibre optic medium is the delay between absorption and re emission of light within the material.

A photon entering the space of an atom has a certain probability of being absorbed. If absorbed, the time for which the photon energy is held depends on factors such as energy of the photon and structure of the atom. Most such photons are quickly released because they have an energy that is wrong for the atom. A quickly released photon is most likely to be emitted in a direction close to its original trajectory, but not always. Optical fibre is a material optimized for this effect. But being released in a backward direction is how reflection exists.

Between absorbtion and re emission in the optic fibre media (which takes a finite amount of time) light travels at it's normal speed.
 
So at the end of the day with all this light speed and not quite light speed, just how long is it going to take my hamburger with the lot to arrive on my desktop and will this absorption thing be an issue or will I have to order it with low cholesterol butter?
 
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Regardless of selling it off, at least if they are legally prevented form selling retail services we would no longer have the situation where the network owner who sells services wholesale to other providers is also directly competing with it's own wholesale customers in the retail market.

Sell it off or not, we'll still end up with a monopoly in the wholesale sector, something we had been slowly getting away from in the last decade. A number of ISPs and other companies have been steadily investing in fibre backhaul links across the country, and now they will in many cases be unable to use those fibres for their intended purpose, reducing their value. Not a real smart way to encourage companies to invest in our country.

I know there's been a lot of technical talk here, but when it comes down to it, theres a fair bit of economics in the mix too. People claiming fibre is better are definitely right from a technical point, but we're going to end up wasting a huge amount of money in the government's current model. The same utility could be achieved for an awful lot less money. Backhaul fibre, fibre to the node, fibre to premises where people wish to pay for it, and wireless available for those who want mobility, continue to use copper for landlines and ADSL for cheaper products, and upgrade down the track when the demand is there. I don't mind people paying for fibre as an option, but don't waste my tax dollars digging it into every house, when half of them won't use it in the next ten years, if then.
 
There are loads of arguments Pinelli about all the points you have raised, but to be honest I have had them on so many fora that I just can not be bothered with it any more. The problem with the NBN is not so much a technical issue, not a financial one, the debate ALWAYS ends up as two opposites who are arguing more from an ideological standpoint.

I (Having worked in the comms industry for a decade) would say that out current state of play is a pretty good example of a failing market. Sure there have been new players, sure there is some competition in infrastructure, but after twenty years, the vast vast majority of the revenue in the industry goes to the incumbent (Telstra) and almost the entirety of the profit. The other players are only ever going to service the high density areas, caus that is where the money is and Telstra has and will continue to play every trick in the book to make things difficult for them.

Also, on the propagation time in fibre, as well as absorbtion and re emission time there is a finite delay due to how fibre is made up.

1: The loose tubes inside the sheath are laid in a wavy pattern that makes them longer than the sheath length of the cable.

2: The actual fibres in the loose tubes are laid in the same way so they are longer than the loose tubes.

Both of these add up to the fibres being measurably longer than "The cable"

3: Added to that is the fact that the light is reflected along the junction between the core and outer section of the fibre at an angle, that means that the light also takes a longer path inside the fibre than the length of the fibre itself.
 
Waveguide propagation theory aside.

The current system doesn't work because Telstra have ownership of most of the infrastructure, copper, exchanges, towers, pits. I believe the new system will be better as 'the people' own the infrastructure and it is up to the ISP or providers to provide a service and compete with each other. I am quite happy as a tax payer to pay for maintenance of this system much the way my parents did with Telecom/Telstra infrastructure when it was gov owned.

They should have followed the Kiwis lead and broken Telstra in half when it was sold. Retail arm to the share holders and infrastructure owned by the tax payers.

At the end of the day it is a step forward and that is better than no action at all. The fibre itself will be take a long time to be obsolete as the technology that sends the light will only get faster and smarter, much like dial-up -- > broadband.
 
Here is me hoping the goverment keep a eye on the building of the network.

The copper network is a disgrace.
 
Waveguide propagation theory aside.

I wasn't trying to start a serious discussion about the speed of light. I guess I see a lot of people that don't see that radio waves etc are also light, and get hung up on fibre optics being faster because they are light, which is as you know, totally irrelevant to the speed and reliability argument anyway. Hence my comment.

The current system doesn't work because Telstra have ownership of most of the infrastructure, copper, exchanges, towers, pits. I believe the new system will be better as 'the people' own the infrastructure and it is up to the ISP or providers to provide a service and compete with each other. I am quite happy as a tax payer to pay for maintenance of this system much the way my parents did with Telecom/Telstra infrastructure when it was gov owned.

They should have followed the Kiwis lead and broken Telstra in half when it was sold. Retail arm to the share holders and infrastructure owned by the tax payers.

I know what you mean about Telstra - absolute bullies. However, we were just starting to reach a situation where there were a number of players investing serious money on infrastructure in competition to Telstra, which would have given some serious competition across the entire vertical structure of the industry. That has now been destroyed, and we won't see it again for a minimum of 20 years.

The problem with the kiwi/us model is you still have a monopoly at the wholesale level, which means inefficiencies, higher prices, and poorer service at the wholesale level. No real impetus to upgrade the backbone, keep it online etc. You don't lose customers if you offer crap service. You don't work harder to reduce costs, because there is no payoff for it. Doesn't really matter if it's a government monopoly or commercial monopoly, same result. You'll end up with a highly unionised, bureaucratic, wasteful organisation (and I say that as a public service long term union member myself). Look at how efficiently the government has been spending money on indigenous housing.

The BER money spent in my town here left our local builders still out of work while the big boys came in from out of town. I have friends screwed over by the surprise policy changes in pink batts installation and green loans. I don't look forward to more of my taxes going down down the drain again.

I've probably said my piece more than enough. I respect that people have different opinions on this, but I have been involved in planning and design of city and state wide networks, both the technology and the finance. The desired outcomes of the NBN could be achieved so much more cheaply, in more complex ways, that would leave large buckets of money of schools, hospitals, roads etc, and still give people and businesses the opportunity to have high speed fibre broadband should they wish, probably at a cheaper price.

Cheerio all, :cheers!:
 
The problem with the "Infrastructure competition" we have been getting is that almost without fail it still uses Telstra infrastructure for delivery.

Aside from wireless services any other delivery method is going to require telcos to dig up the street and put in fibre to each new customer on an ad hoc basis (Although when I worked for Optus there was a lot of forwrd thinking that went into that so if you connected a customer you went and talked to the network planners and asked what they wanted out of it for future needs) and that costs huge money. I can tell you that $50K does not go very far.

If you are not going to dig up the street then you are stuck with using Telstra infrastructure for delivery, instead of charging $70 a month to the end customer and handing over $65 of it to Telstra for the wholesale service (Figures plucked from bum here, not actual figures) you pay telstra $10 a month for the space for the DSLAM, plus leases for the space your backhaul fibre takes up in the cable trays, plus most likely duct lease costs plus leased line costs for the telstra owned copper to deliver the service to the end user over. win win win for Telstra every way you cut it.

the problem with the seperated model is just what you said, particularly if the network is privatised, but Australia just does not have the population density to support real infrastructure competition. We are gonig to have a backbone monopoly if we like it or not, the question is do we want a new monopoly with (Currently) near state of the art technology behinnd it or an old one tryinig to wring the last cent out of a network that is 50 years old and more and beginning to crumble around us with no sign that they plan to upgrade it.
 
People, before we get too ahead of ourselves here, let's not kid ourselves by thinking that because the infrastructure is "taxpayer owned" that the wholesale "rental" will be lower cost than what it would be if it were private sector owned. The government knows how to exploit a cash cow when it sees one.
 
If you are not going to dig up the street

I heard that they were going to sling the fibre on aerials in situations where the street was already supplied via o/head power/comms/cableTV. I can see how that seems like an economical solution and speedy delivery, but is it really a long term solution? The days of power poles are numbered, overhead power is dangerous, prone to damage by vehicles etc, and every time we get a storm, the network gets fried - hence why most supply authorities have plans to gradually replace overhead networks with u/ground over the next "X" years. Rather than replacing a few poles in a street they will just re-route everything underground.

So then we'll be doing the fibre again too.
 
Well i imagine with a litttle cost cutting in mind. The NBN Co. will simply pay a small fee to place its cabe under ground the the power company digs up the street. It's not like they have to dig seperate holes?? Besides drunk dickheads crashing into power poles, i think it seems like a reasonable idea.

Fibre does not suffer from EM interference the same way copper does.

Do you think that they would burry the power cable, fill the hole in and then come back a day later and dig it up again to bury fibre?
 
Being an electrical engineer I'm pretty well up to speed with the basics of all that, thanks.

As ridiculous as it sounds, it is in fact quite possible that the two authorities wouldn't work together and they may dig two trenches. Our biggest headaches designing projects comes from supply authorities and telecomms carriers (with comms carriers being far and away the worst)
 
It has nothing to do with the supplyauthority, but everything to do with digging up/damaging the other stuff. No too many comms techs want to be wielding a shovel when there is 415V in the same trench.
 
It has nothing to do with the supplyauthority, but everything to do with digging up/damaging the other stuff. No too many comms techs want to be wielding a shovel when there is 415V in the same trench.

Maybe they could hitch their skirts up a bit and just get stuck in to it :dancing1:
Lol
 
Actually, if the NBN criples or kills off optarse, it would be worth it whatever the price. Had another one of the droppings from the Indian sub-continent interrupt my work on the Nav by telling me he was from our local telephone exchange. "Lying bastard" brought out an optarse identification card. Had to tell the thick bastard three times to get off the property.
 
The problem with the "Infrastructure competition" we have been getting is that almost without fail it still uses Telstra infrastructure for delivery.

And we were starting to get away from this. Optus, 3, iinet and others have been busy spending squillions of dollars putting in backhaul fibre across the country. And now they have been told they can't use it for general internet use, except under certain conditions. Why? Because if would compete with the NBN. Now the government is expecting private industry to invest in the NBN???:suicide2:

And to back up Wir35, it's bloody hard to get various authorities to share trenches. Telstra had a campaign at one stage (Just One Trench - you could get a t-shirt if you wanted:big_smile:) trying to organise just this very thing. I don't know how much success they had.
 
From the local exchange. Lol.

There all un-manned except for the huge ones in like Sydney, Melbourne etc.

Some of the hut's down here have like 150 pairs and a few pairs gains sytems and thats it.

Id love to see those RIM's and CMUX's manned.

Lol.
 

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