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Re: Installing ?!


Hi. 

A proxy is something that does something on your behalf while
appearing to be the real thing.

An HTTP Proxy would be something you'd connect with, tell it to view a
website, and the Proxy responds with the information *as if* it came
from the original website.

CLIENT <------> PROXY <------> Web Site (http://www.yahoo.com/)

Let's say I'm the client and I want to view Yahoo! If I'm directly
connected to the internet then there is no proxy, so it would look
like this (not 100% accurate but good enough for right now):

CLIENT <---------> WebSite (http://www.yahoo.com/)

But let's say I work at a very large company with a very large number
of employees who are looking at yahoo maybe 10 times a second at
various times of the day. Since it is unlikely that Yahoo will change
within that 1 second, we can pretty much assume that all these people
viewing Yahoo! during the same second will see the exact same page.

A proxy could be installed between the internet and the employees'
computers which, when contacted, determines if it has a copy of
Yahoo's default webpage in it's cache (in memory or on disk). If it
doesn't, it contacts Yahoo and caches the webpage and sends a copy
back to the client (employee computer). OTOH, if it does have a copy
of it then it just sends the copy of it meaning that end user's
response time is quicker and internet usage is lowered.

Mahlon Hull <xavier_827@yahoo.com> writes:

> directory and hit next. Then it asks me to select my internet
> connection, this is where the fun begins.  First of all I don't know
> what the options mean: direct connection, use ie5 settings, and use
> http/ftp proxy.

A direct connection basically means a normal connection to the
internet. For example, if you're connected to the internet (even via
PPP), you could run "command.com" and ping yahoo.

If there are some strange settings in InternetExplorer5, such as proxy
settings, then you would want those settings. So setup.exe queries the
networking information stored for IE5 and uses them to contact the
sites to download information.

If, OTOH, you know your proxy information yourself and perhaps aren't
using IE5, then you could just type it in.

> First of all what does direct connection mean, am i supposed to be
> on the internet when I try to do this (I'm guessing yes)

Yes.

> or does this dial them up directly (I doubt this) or what?

It may. This could probably be best answered by someone who knows
setup.exe internals, but to the best of my knowledge Windows
Networking does something like this:

1) Application makes a network query
2) Windows sees this and determines if a connection is available

If a connection is available then jump to step 4, else step 3

3) Windows connects to the network in a default way (such as via PPP)

4) Windows provides networking service to application

But if you aren't connected to the internet when you use this option
and Windows starts dialing out, then you know that Windows is doing
step #3 and trying to make a connection to Cygwin (or a mirror) via
the internet.

> Second I have Internet Explorer 6 not 5, I'm assuming that ie5
> stands for Internet Explorer 5.

Yes. But Proxy information may be contained in Internet Options so
perhaps someone just put IE5 and meant "Default Internet Options as
you would receive using Internet Explorer 5".

> And lastly what are you supposed to put in the proxy host box and
> the port box if you select that option?

Your proxy host and proxy port.

CLIENT <------>      PROXY       <----------------> www,yahoo.com
              Listens on: 
                  IP Address: 192.168.0.1
                  port # 8080
                       
Client would connect to proxy at 192.168.0.1, port 8080 that contacts
yahoo on client's behalf.

> Anyway I have selected the first two options and all I get is this
> error:
> 
> Can't get list of download sites.  Make sure your network settings
> are correct and try again.

It's unable to connect to the site and retrieve a listing of download
sites. 

> What does that mean?

For some reason your computer is not able to connect to Cygwin's main
site and retreive a listing of download sites - that is, sites that
have the actual software you would download (the packages) for running
Cygwin.

Why aren't they on the same host?

To help throughput and internet costs. By placing the downloadable
material on different servers, you could, for example, choose a site
closer to your geographically - meaning the packages will arrive on
your computer quiker. Plus, by a group sharing the downloadable
packages, the network traffic is divided up so that costs are
distributed somewhat.

Also, if many people were trying to download from the same site, there
may be delays in that a server can only do so much.

> And I'm sure you'e figured out that I don't know how to use the
> third option but I'm sure even if I did it would give me the same
> error.

You probably don't need it for your scenerio. If you have your
internet connection set up in a fairly normal way then you'd use
"Direct Connection".

> Anyway if someone could give me some insight as to why I'm having
> this problem it would be greatly appreciated. Oh, I do not know if
> this makes a difference or not, I don't think that it would because
> the website says that this opperating system is "expected to run",
> but I have Windows XP Professional Edition.

It works fine in Win98.

Elizabeth

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