[gurps] Re: Internet on blue planet and like worlds

[David Scheidt]

On Thu, Jan 1, 2009 at 10:18 PM, Jeff Wilson <jwilson at io.com> wrote:
> From: "David Scheidt" <dmscheidt at gmail.com>
>>>
>>> > David Scheidt wrote:
>>>>
>>>> >>
>>>> >> For communication between fixed points, cables will always be cheaper
>>>> >> than radio links in the the long run.  They're also faster and more
>>>> >> reliable.
>>>> >>
>>>
>>> >
>>> > I'm not sure I can agree with you unless you specify the distance
>>> > between
>>> > the fixed points and whether you can rig masts for additional range due
>>> > to
>>> > LOS issues.
>>> >
>>> > If you have LOS, then point to point wireless communications is much
>>> > less
>>> > expensive, both in the short run (setup costs) and long run
>>> > (maintenance
>>> > costs).  If you're looking at distances of several hundred miles and
>>> > can use
>>> > solar/battery powered relays, then you're still going to be less
>>> > expensive
>>> > over running cable between the two fixed points.
>>
>> There's a reason there are no long-distance microwave links anymore:
>> They're expensive to run (radios consume lots of power), they're
>> expensive to maintain, they're unreliable, they're weather sensitive,
>
> I think you're overlooking advances in DSP and other fields. A kitbashed
>  cantenna will push an off-the-shelf wifi connection to 10+ miles, and all
> the larger public schools here in Texas' 8th region are connected via dish
> and mast to regional HQ in Mt. Pleasant (50 mile radius; though the weather
> here is very mild during the school year, I will admit).

That's not very long distance.  Nor is it very high speed.  Nor is it
terribly reliable, as directional antennas are sensitive to alignment
issues (and as range goes up, so does this problem.)  Things have
improved, sure.  But if it made sense, would T and MCI have turned
down all their existing (and fully depreciated!) MW backbone?  I've
got my doubts.  Remember, in the same time period installed fibre has
had its capacity increase by several orders of magnitude.

Wireless makes all sort of sense for short distances, (relative) low
speed, and mobile use.
It doesn't make sense for point-to-point use, in the general case.

-- 
David Scheidt
dmscheidt at gmail.com