The http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem limits the information that can be transmitted through a given channel. If you want to send more wired data, you add more channels by adding more wires. Wireless doesn't have that luxury.

Strictly speaking this is true, however you can add more base stations with lower transmit power so the shared media is shared by lower number of clients. This is what is already done in urban areas with smaller base stations.

Are you able to expand? I tend to agree but dont really know why or what / where the physical limits are. Is it the 4g etc tech that can't perform with real load or WiFi that will fall over? Is a mesh network an answer?

The problem is that wireless is a shared medium. If you have a certain amount of spectrum, you can transfer a finite number of bits per second using it, and that capacity is shared between all devices in range. The bandwidth available in a certain chunk of spectrum is a physical limit. There is no way to expand capacity other than by allocating more spectrum, and radio spectrum is extremely scarce. So the more users you have using cellular for internet, the less bandwidth they each get.

The solution when you want to have "wireless" devices but there isn't enough wireless spectrum is to use wireless for the "last 50 meters" rather than the last mile. In other words, you have fiber to the premises and then WiFi within the building. By keeping the wireless power levels as low as possible you reduce the number of other users you're sharing the spectrum with and allow each user to have a satisfactory amount of bandwidth. Then reserve cellular wireless for users not in a building, e.g. accessing a map from your car, and have all manner of stupid bandwidth caps to discourage usage of cellular wireless whenever it isn't strictly necessary.

> Is a mesh network an answer?

No. Mesh networks would allow you to have more bandwidth per user by reducing wireless power levels and shrinking the geographic size of the collision domain, but that would require peers to act as repeaters between other peers and the tower. That's an epic fail. It adds latency, reduces battery life, impacts reliability if any peer's device is flaky, has security implications, etc. Wireless mesh networks ironically work much better for fixed-position devices than mobile devices, because they can use directional antennas, don't have the extreme power constraints mobile devices do, etc.

It all depends how much bandwidth you need for a given use case. For most use cases other than video, existing wireless technologies are sufficient and will only continue to improve as things like beam shaping and micro cells become more prevalent. Wireless is easier to deploy and as its use grows, more spectrum will likely open up. Free markets have the benefit of deploying scarce resources where they are most in demand. Implementing that spectrum is often as easy as a configuration change that can be deployed remotely.

The biggest advantage of a wired home broadband connection over a wireless one that I see is the ability to stream video. A wired connection has a lot of disadvantages: it's useless outside the home and the infrastructure is significantly more expensive. Wireless has signal and coverage issues for sure, but wireless is a much more competitive industry than wired access in no small part because it's cheaper to deploy.

I don't think it would be going out on a limb to say the HN audience is much wealthier and more technology-literate than the average citizen, and thus would be more likely to want multiple Internet connections and have more use cases such as running file servers, etc. I think the HN crowd overestimates what people use their Internet connections for; the average person uses their home broadband connection primarily to watch video. It's not a bad use case by any means; but I'm not sure the government needs to be building infrastructure that will be primarily used by video streaming companies. Traditional cellular wireless (which can use any mix of wireless, wired or satellite backhaul depending on the application) and Wi-Fi are flexible enough to cover the "access" part of Internet access; especially in an increasingly post-PC world.

> For most use cases other than video, existing wireless technologies are sufficient and will only continue to improve as things like beam shaping and micro cells become more prevalent.

Excluding today's most demanding use case doesn't get you anywhere. If you need a wired connection for that then you need a wired connection. The installed base of smartphones and tablets is still growing significantly and that's going to eat any technological improvements you can make to cellular and then some. Meanwhile people still want to be able to watch Netflix on a tablet from the back of a minivan, and to be able to make that happen at scale you're going to have to remove as much other traffic from the cellular network as possible.

> Wireless is easier to deploy and as its use grows, more spectrum will likely open up. Free markets have the benefit of deploying scarce resources where they are most in demand.

Free markets can't change the laws of physics. Allocating more spectrum is a linear increase. 20% more spectrum costs billions of dollars and only makes it 20% faster. The market solution when there is a high demand scarce resource is to shift usage to a resource that isn't as scarce for any use case where the alternative resource is viable. There is a reason one of the first things you already do when you get to a friend's house for the first time is ask for the WiFi password, and it's not because there is no cellular coverage.

> The biggest advantage of a wired home broadband connection over a wireless one that I see is the ability to stream video.

The advantage is that it allows you to transfer more bits cheaply. Today's most prevalent use case for that is streaming video, sure. It's hardly the only one. Anything that requires uploading or downloading large amounts of data is a bad fit for cellular. And we can't predict what interesting applications will become commonplace once the typical connection is 1Gbps.

> A wired connection has a lot of disadvantages: it's useless outside the home and the infrastructure is significantly more expensive.

The infrastructure is significantly more expensive, once. The cost to maintain fiber is not materially different than the cost to maintain copper. And it's not useless outside the home when everybody else has one too. If you're at home you have WiFi. At work? WiFi. Friend's house? Coffee house? Hotel? WiFi. About the only fixed places there is no WiFi are the places there is also no cellular, like the middle of the woods.

Using cellular when you're in a building with WiFi doesn't make sense. Using cellular when you're on the move does -- and that's the use case we should be preserving the scarce wireless spectrum for, by using wired connections everywhere else.

> The cost to maintain fiber is not materially different than the cost to maintain copper.

You're right; and costs to maintain copper run about 5-10% of initial costs PER YEAR. Physical networks with lots of endpoints are very expensive to maintain.

> You're right; and costs to maintain copper run about 5-10% of initial costs PER YEAR. Physical networks with lots of endpoints are very expensive to maintain.

We already have physical networks. Maintaining them is a fixed cost.[1] You can't eliminate it because you can't reasonably expect to replace the entirety of Cable TV and U-verse with cellular, so the money might as well be going to maintain fiber rather than copper.

[1] http://en.wikipedia.org/wiki/Fixed_cost

$300-500 billion is a lot to install a national fiber network because "we might as well". If they're going to cost the same to operate, what do we get in exchange for this $500 billion investment? The ability to watch Netflix videos at a higher quality? A slightly lower cable bill? (since the cost to maintain won't be significantly lower, the bill won't be either)

I'm not trying to be sarcastic here -- this is how the government thinks about things. We have an existing infrastructure that is less than optimal, but it still functions and is in no danger of imminent collapse. Contrast with our healthcare system which barely functions and is on the verge of effective collapse. Or our public schools and police departments, which have collapsed in a number of cities.

In short, it's hard to drum up political support for large infrastructure projects even if you can show the need. There has to be a demonstrable catastrophic impact if we don't do the project, which just isn't the case with broadband.

Thanks mostly confirming what I suspected. I did think we would be able to use the spectrum more efficiently over time with better, more precise measurements but my guess is that will scale to its own limits a lot faster than a hard line will.

Much like procesing power and moore's law, we're getting very close to shannon's law (http://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem.

Wireless isn't this huge gamechanger that people may think. To beat shannon's law you would need so many base stations in the long term it looks awfully like what we have now with DSL/Fiber/DOCSIS and wifi APs.

Wired connectivity certainly isn't either. I find myself using my home internet connection almost exclusively for movies and games -- not exactly the great innovative services everyone talks about.

I use my phone for almost everything else: online shopping, communication, news consumption, even work since I tether my laptop to it when I'm on the go. It's a lot more convenient; and the only thing I really need high bandwidth for is media playback.

How do you think your wireless signals get to the rest of the world? Microwave backhaul is almost dead, those cell towers (and there are tons of them in urban environments, partly for want of spectrum) are wired up with fiber.

Of course wired is used for backhaul between wireless nodes and the internet; but I'm speaking as a consumer technology. Wired access is definitely here to stay for infrastructure uses.

exactly. Plus even if I'm on my phone I prefer the speed and reliability of my own Wi-Fi.