Skype on a Toshiba notebook.

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?

Irwell wrote:
> 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/FA1...n-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/route...327W/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

On 30/07/2011 04:37, Paul wrote:
> Irwell wrote:
>> 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.

For someone who doesn't use Skype you sure write a lot of what will most
probably be completely useless.

Let him just install Skype and get on with it.

I have Skype on my W7 machine and it installed in a jiffy. No problems
whatsoever. But in any case let him install Skype and then ask for
solutions if any problems crop up.

You don't cross your bridges until you come to them.
-- choro --

>
> 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/FA1...n-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/route...327W/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

choro wrote:
> On 30/07/2011 04:37, Paul wrote:
>> Irwell wrote:
>>> 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.
>
> For someone who doesn't use Skype you sure write a lot of what will most
> probably be completely useless.
>
> Let him just install Skype and get on with it.
>
> I have Skype on my W7 machine and it installed in a jiffy. No problems
> whatsoever. But in any case let him install Skype and then ask for
> solutions if any problems crop up.
>
> You don't cross your bridges until you come to them.
> -- choro --

What ports does Skype use then ?

Paul

Paul wrote:
> choro wrote:
>> On 30/07/2011 04:37, Paul wrote:
>>> Irwell wrote:
>>>> 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.
>>
>> For someone who doesn't use Skype you sure write a lot of what will
>> most probably be completely useless.
>>
>> Let him just install Skype and get on with it.
>>
>> I have Skype on my W7 machine and it installed in a jiffy. No problems
>> whatsoever. But in any case let him install Skype and then ask for
>> solutions if any problems crop up.
>>
>> You don't cross your bridges until you come to them.
>> -- choro --
>
> What ports does Skype use then ?
>
> Paul

OK, found what I needed.

The reference to port 80 and 443 is outgoing (which is not blocked by
a home router as far as I know). This article, however, doesn't refer
to that incoming port I was referring to. But at least this article
describes some of what goes on.

http://en.wikipedia.org/wiki/Skype_protocol

This is a paper, where some academics study Skype traffic.
On page 10, the section "PAYLOAD-BASED SKYPE TRAFFIC IDENTIFICATION"
second paragraph is interesting.

ftp://gaia.cs.umass.edu/pub/Suh05_relay.pdf

"Before describing the heuristic, we first give some details about
the functionality of Skype."

That description is a bit more useful than the Wikipedia dump.

There is still a part missing. But then it occurred to me, I should
be looking for "NAT traversal", because if that port I was referring
to wasn't open, there has to be some other mechanism for people
who don't know how to set up their router.

So this is the answer...

http://forum.skype.com/index.php?showtopic=2008

"I think the basic concept is that if both machines are behind NAT,
then they need to connect through a third party that is not behind a
NAT (or at least has the port open so it can accept connections from
both machines).

The third party acts as a open pipe for the two machines to talk
through. This, of course, can create inefficient routing since to
get packets to/from the two machines, it may have to take a longer
route through the third machine.

That's why in the FAQ they recommend opening up the port... so at
least one of the machine can act as the server to host a
direct connection. I think it attempts direct connections to/from
both machines before it looks for a third party to host.
"

So what I learned from this exercise is:

1) If you use Skype, and remove all blockage to the Internet (connect
directly to modem, no NAT), your machine could be used as a SuperNode
or a "higher element" in the Skype network. Connecting computers
directly to the Internet isn't really a recommended configuration
anyway, so this is purely academic. Nobody in their right mind would
turn off the firewall, and just connect a Windows PC directly
to the Internet.

2) If you have a router or some NAT layer, you can punch a hole in it.
Port forwarding the "random port" shown in the Skype preferences,
that *may* avoid the usage of a relay machine. Perhaps that is the
reference to "better performance" ?

3) If you don't punch the hole (the "Choro approach"), then it all
still works. It just uses the Skype NAT traversal solution.

So option (3) is certainly reasonable, with option (2) if you
aren't happy with the results, and would like to try something
else.

HTH,
Paul

Paul wrote:

One other item I found. Skype has its own kind of malware :-)
This is via Skype Instant Messaging (IM).

http://www.cert.at/static/downloads/...nality_1.2.pdf

That is a paper from:

http://www.cert.at/downloads/papers/skype_imbot_en.html

It's possible to get malware over Skype, if you put your mind to it.

The author of that paper recommends:

"Recommendations and proposed steps

For affected Users

* Do not blindly click on a link coming from "your best friend".
Use the same reasoning in Skype as when receiving mail from a friend
with an attachment. Users are already a little bit trained to not
trust every email attachment. Similar caution should be used with
Skype or other social media platforms.

* Do not run Windows XP as Administrator. Use a separate user account.
"

Fun stuff,
Paul

Paul wrote:

> What ports does Skype use then ?

IM(L)E it tries all manner of ports until it finds one that works!

Hi

"Irwell" <> wrote in message
news:ue04a4s7xt91.18xbbdg49nndq$....
> 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?

Yes it is very easy, just go through the privacy settings and
alter them to your requirements.

Trevor

Paul wrote:
> Paul wrote:
>
> One other item I found. Skype has its own kind of malware :-)
> This is via Skype Instant Messaging (IM).
>
> http://www.cert.at/static/downloads/...nality_1.2.pdf
>
>
> That is a paper from:
>
> http://www.cert.at/downloads/papers/skype_imbot_en.html
>
> It's possible to get malware over Skype, if you put your mind to it.
>
> The author of that paper recommends:
>
> "Recommendations and proposed steps
>
> For affected Users
> * Do not blindly click on a link coming from "your best friend".
> Use the same reasoning in Skype as when receiving mail from a friend
> with an attachment. Users are already a little bit trained to not
> trust every email attachment. Similar caution should be used with
> Skype or other social media platforms.
>
> * Do not run Windows XP as Administrator. Use a separate user account.
> "
>
> Fun stuff,
> Paul

Paul, when Choro read that he ran away crying :-)

On 30/07/2011 11:53, Seum wrote:
> Paul wrote:
>> Paul wrote:
>>
>> One other item I found. Skype has its own kind of malware :-)
>> This is via Skype Instant Messaging (IM).
>>
>> http://www.cert.at/static/downloads/...nality_1.2.pdf
>>
>>
>> That is a paper from:
>>
>> http://www.cert.at/downloads/papers/skype_imbot_en.html
>>
>> It's possible to get malware over Skype, if you put your mind to it.
>>
>> The author of that paper recommends:
>>
>> "Recommendations and proposed steps
>> For affected Users * Do not blindly click on a link coming from "your
>> best friend".
>> Use the same reasoning in Skype as when receiving mail from a friend
>> with an attachment. Users are already a little bit trained to not
>> trust every email attachment. Similar caution should be used with
>> Skype or other social media platforms.
>>
>> * Do not run Windows XP as Administrator. Use a separate user account.
>> "
>>
>> Fun stuff,
>> Paul
>
> Paul, when Choro read that he ran away crying :-)

You're probably right.

Paul gives his all here; he obviously spends ages researching each new
topic, and writes up his major findings for all to see.
I find that admirable. It should get more appreciation as socially
beneficial.
It's not for ppeople seeking a quick fix; it's for people who want
genuine knowledge and understanding of these boxes of tricks.

Ed