Broadband From The Sky In 2002?

Krendle writes: "A company named ISky is claiming that they will deliver high speed (2mbps down, 1/2mbps up) 2-way satellite Internet access by the end of 2001. One issue I've seen raised in newsgroups (in reference to satellite internet in general) is that of lag. With Internet applications like telephony and online gaming, etc., gaining popularity this is an important issue. 2Mbps from the sky still sounds cool to me, especially where we can't even get cable TV. What do you guys think -- will latency be a problem?" I'd be happy to "settle" for always-on wireless access faster than dial-up and cheap as DSL, but the iSKY Q&A page is short on price details. But it does say "iSKY is planning on being able to support all platforms including Macintosh, Linux, Solaris and Windows."

Comments

This is neat, but reaches limits very quickly.

[Christopher Thomas]

Satellite 'net access is a very cool toy, and is extremely useful for ares that don't offer cable/*DSL (everywhere except large cities, in other words).

However, don't expect satellites to replace cable any time soon. There are difficulties when you try to scale up to the silly bandwidth levels required:

• Area served by one satellite is large.
  Your satellite is at least 300km up, and making microwave beams really parallel is tricky (unless you want to use a huge dish, which adds weight and cost to the satellite). This means that, even pulling tricks like having multiple fairly-narrow-angle transcievers per satellite, you still get everyone within a few tens of kilometres sharing the same uplink. Fine for low-density areas, but not for cities.
  
  
• Bandwidth is bad compared to fiber.
  Microwave beams have a data bandwidth comparable to their frequency - a few Gbits/sec. at most. This is the maximum _shared_ bandwidth per uplink region, and the maximum bandwidth of the pipes between the satellites. Bump the frequency up to get more bandwidth, and you start getting blocked by light cloud cover and thin walls (and ceilings). While you could do something like have an optical link from satellite to satellite, your uplink/downlink bandwidth is going to be pretty crummy compared to, say, a fiber backbone serving the same area.
  

I'm not trying to bash satellite data services - as mentioned above, they do have their uses. I'm just trying to stave off the inevitable flood of "Wow! Now everyone in the city can get cable bandwidth from their palm-pilots!" messages.

Geosynchronous orbits: 250ms latency.

[PeterM from Berkeley]

Their web site says their satellites are in geosynchronous orbits.

Geosynchronous orbit is 37500 km. This translates into a minimum roundtrip speed-of-light latency of 250ms.

Any netrek player will tell you that that amount of latency is too high for effective gaming!