Working in rural Alaska for a number of years I have seen the bandwidth to schools and homes increase exponentially, been present for teleconferences across the globe (I just missed the VTC to outer space in SWRSD), and now have a cell phone with data faster than my first satellite based ISP!
With all this change the question is still asked of me: "Why is the internet so terrible in the Bush?" or "Is there anything we can do to make it faster?"
Faster is a difficult concept to nail down though. Let's start with some vocabulary.
Bandwidth - a measurement of bit-rate of available or
consumed data communication resources expressed in bits per second or multiples
of it (bit/s, kilobit/s, Megabit/s, Gigabit/s, etc.)
Latency - a time interval between the stimulation and response, or,
from a more general point of view, as a time delay between the cause and the
effect of some physical change in the system being observed
If you need help understanding, let me put it
this way: You are in the typical village in Alaska trying to Facebook chat, listen to Pandora, and download a movie on iTunes for entertainment later tonight. Your movie started out with a 3 hour download time, but after you clicked on Facebook and opened the chat window it slowed and now it says 3 hour and 15 minutes. This is your bandwidth. Once you launch Pandora you click on your favorite channel and it takes forever to load... this is both bandwidth and latency. You're frustrated, so you chat your friend to tell them the internet is too slow, but the message is delayed and it's hard to explain to your pal in Los Angeles. Thinking it better to just call them, you pause Pandora and Skype them. The connection bumps your movie to 5 hours now and your connection is grainy and pixelated. There is an echo when you talk and a big delay, this is latency.
In the case
of satellite-based internet we have two more issues to
understand.
Packet Loss - the loss of data segments in the
transmission (caused by programming, decoding, or physical irregularities)
Jitters - the loss of signal due to
environmental influences (something is in the way of the dish, obstructing the
path of the signal
An example of this follows the earlier one except your download times out even though Pandora was streaming the whole time. This was an example of jitters, or an unexplained drop in the connection, one that didn't even register with Pandora, but caused your Skype to go offline for a second and error your download.
So if satellites are so bad, why not try something else? Alaska did just that: they ran a fiberoptic ring around the state and where they couldn't run cable they linked microwave towers. This system produces a signal more reliable, less dependent on weather, and with a faster connection. How much faster? Well the ISP for LYSD currently the has a 1000-1900ms latency, or time from one village to Anchorage (and the outside world) and back. The alternative is generally closer to 30-60ms. We're measuring in milliseconds here, so don't go crazy just thinking of the numbers...
This terrestrial system is limited by the weakest point in the ring, which I am often asked about as well. Many villagers, myself included, are residential customers of this service. Our signal drops, the access goes down, and sometimes even the transmitter/tower in town needs replacement. This is not a break in the service to the village, though. We are experiencing a failure in the delivery of the service from the mainline to our home via cellular transmission towers. The backbone is still up though 99% of the time. The microwave towers and fiber are extremely reliable.
"But if the fiber ring is dependent on microwave transmitters/receivers, aren't those just physical dishes, just like the satellite systems of other ISPs?"
This is a little complicated. Yes, in a way, but no, resoundingly, they are not the same. Transmitting a signal across a nearly line-of-sight is nothing compared to two trips through the atmosphere. Think about that for a second. You click a link and send a signal to an orbiting satellite, floating around the planet, then bounce it to Eagle River, AK which receives the signal and passes it on to the rest of the world... The server on the other end sends you back a signal in the same way and you enjoy the webpage or action expected. That's pretty amazing in itself, rght?! The real question here is how fast is a microwave transmission.
So if satellites are so bad, why not try something else? Alaska did just that: they ran a fiberoptic ring around the state and where they couldn't run cable they linked microwave towers. This system produces a signal more reliable, less dependent on weather, and with a faster connection. How much faster? Well the ISP for LYSD currently the has a 1000-1900ms latency, or time from one village to Anchorage (and the outside world) and back. The alternative is generally closer to 30-60ms. We're measuring in milliseconds here, so don't go crazy just thinking of the numbers...
This terrestrial system is limited by the weakest point in the ring, which I am often asked about as well. Many villagers, myself included, are residential customers of this service. Our signal drops, the access goes down, and sometimes even the transmitter/tower in town needs replacement. This is not a break in the service to the village, though. We are experiencing a failure in the delivery of the service from the mainline to our home via cellular transmission towers. The backbone is still up though 99% of the time. The microwave towers and fiber are extremely reliable.
"But if the fiber ring is dependent on microwave transmitters/receivers, aren't those just physical dishes, just like the satellite systems of other ISPs?"
This is a little complicated. Yes, in a way, but no, resoundingly, they are not the same. Transmitting a signal across a nearly line-of-sight is nothing compared to two trips through the atmosphere. Think about that for a second. You click a link and send a signal to an orbiting satellite, floating around the planet, then bounce it to Eagle River, AK which receives the signal and passes it on to the rest of the world... The server on the other end sends you back a signal in the same way and you enjoy the webpage or action expected. That's pretty amazing in itself, rght?! The real question here is how fast is a microwave transmission.
"[New
York-based networking company] Strike, whose ranks include academics as well as
former U.S. and Israeli military engineers, hoisted a 6-foot white dish on a
tower rising 280 feet above the Nasdaq Stock Market's data center in Carteret,
N.J., just outside New York City. Through a series of microwave towers, the
dish beams market data 734 miles to the Chicago Mercantile Exchange's computer
warehouse in Aurora, Ill., in 4.13 milliseconds, or about 95% of the theoretical
speed of light, according to the company. Fiber-optic cables, which
are made up of long strands of glass, carry data at roughly 65% of light
speed."
The bottom line is ISPs in the Bush will always have a monumental challenge on their hands. For users, the only option is to appreciate what you have, use it to the fullest, and have a backup plan when things are not working.
I hope this all made since and that you do not disagree with my analogies. If you have questions or corrections, please email me.
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