Irwell said:
My wife, a novice in computers, has a new Toshiba with W-7 starter.
There is a built in camera.
Is it pretty straightforward to use Skype on this set-up?
First off, I don't use Skype, but I have some ideas as to
what will be needed.
That depends a bit, on what other networking boxes are between
your wife's laptop, and the Internet. If your wife connected
the laptop *directly* to a modem device, which had no routing
function, you might not have to do anything in that case. But
you'd also receive the advice, to have the Windows Firewall turned
on for sure, if you were doing that.
Most people are usually behind some kind of wired or wireless router,
and have multiple computers sharing a single broadband modem.
This article
https://support.skype.com/en/faq/FA148/Which-ports-need-to-be-open-to-use-Skype
implies that one incoming port must be opened and port forwarded,
to the computer that is going to be doing the Skype. Since each
Skype user, sitting in front of their own computer, can define
their own incoming port, you could port forward separate ports
to different computers. The port number must be greater than
1024, for this choice, according to the support.skype.com article.
--->
Port forward 34249
ADSL or ------- router (either ------------------ Computer #1
cable modem separate or part Port forward 34250
of the modem) ------------------ Computer #2
Port Forwarding, is something you set up inside the router,
using the web based router configuration. You might also need to
set up the Firewall within the Computer OS itself, to pass
the traffic on that port.
A good application, during installation, will mention the
dependencies. It would be dangerous for an application to be
"over-automated" and start messing around on its own. So I expect
there is some tiny amount of work necessary by the user. While
the protocol stack may have fall-back protocols of some sort,
the performance might not be the best. And for someone outside
your router, to make a "call" to you, some hole needs to be
punched to make that possible. Otherwise, your computer would
have to poll a central server at regular intervals, to determine
if a call is pending, and that doesn't scale particularly well
when there are millions of subscribers.
As it is, the protocol somehow needs to record your IP address,
so there is some way to commence a connection from the outside.
My public Internet address is assigned dynamically by the ISP,
when I start my modem in the morning, so my "new" address would
need to be sent to Skype call control, in order that any future
connection would be known. Either that, or something like dynip
would be needed, if Skype chose to use symbolic addressing.
This is an example of setting up a port like the "34249" in
the example above. The reason they investigate the preferences
in Skype first, is Skype assigns a port randomly, so they're choosing
to use the random value. But I gather, you can also change this,
if the chosen random port, conflicted with some other incoming
port usage you had set up.
http://portforward.com/english/routers/port_forwarding/Westell/Versalink327W/Skype.htm
Since I don't run any "servers" here at home, I have zero ports
forwarded via my router. That is called "stealth mode", when done
in a certain way. Opening port 34249, means script kiddies will be
able to get a response from that port, once the Port Forwarding
is set up, and the laptop is booted. Presumably the Skype software
will be listening for that port, and respond when a packet comes
in.
It would be nice, if there was a clearly written article about
protocols and ports, but that seems to be wishful thinking
with Skype. I think I've tried looking for this info in
the past, and all I got was frustration for an answer.
Skype has to do many of the same things as VOIP or other
forms of digital telephony, so there should be a few
interesting details involved.
In the first link above (the support.skype.com one), they mention
incoming port 80 or port 443 being "alternatives", and I don't see
how that is possible, unless the router has those port forwarded
as well. Outgoing 80 or 443 is another matter. And if your ISP
sees you accepting traffic on port 80, there first hunch would be
you're running a web server
Some ISPs don't like that, as
they want to charge you for a business connection if you do that.
And this is why, I'd like that Skype article dumbed down a bit,
and spelled out in more detail. Sort of like the portforward.com
site does, for various things.
Paul