Skype users?

I use Skype for conference calls, instant messaging and regular phone calls with people all over the world. I manage a team of developers in the Ukraine, my client is in Toronto and I am in Seattle.

The Skype to Skype conference call service is easy to use and the call quality has been excellent. Better than many of the conference calling services I've used in the past. I have a Skype compatible headset plugged into my computer (available from radio shack or online).

I also make calls to other Skype users and receive them as well, again the call quality has been good.

It is possible to pay for a number and receive calls from phones but I have not used that feature. It is also possible to forward calls to a cell phone - again I haven't done that either. I do know that Michael Max uses his Skype number to receive calls while traveling in China and really likes the service.

Yesterday, I found software to allow me to send and receive Skype IM from a smartphone called IM+ and was wondering if anyone has experience with the software.

Brianna,

I use skype's unlimited plan and have since January.

At the time it was $30 per year and included Skype-out (call phone numbers), Skype-in (incoming phone number) and voicemail. I use it exclusively to call actual phone numbers. If you called my skype number (206) 201-2804, you would get me on my computer.

Try it, I dare you! :)

I have been working with a client who is going to start using Pamela Professional Edition, which is a Skype add-on / standalone build that features call automatic recording and storage for compliance purposes. You can also buy a wi-fi enabled skype phone and use it around the house or at the local coffee shop with a wi-fi hotspot.

Many smartphones are now sporting versions of skype that you can use over wi-fi to save on cell minutes.

I hope this helps!

You may use the service with a hybrid phone. There are several models available. Follow this link here to get to them.

Bill

Like Bill I have used SKYPE Unlimited for about 8 months. And over all I've been very happy with it. The separate phone number has been a big help. I've only had one issue, for about a day, where calls were not going to the voice mail feature when I wasn't around to get the call. The conference call feature is excellent and only occasionally glitches out where one person on the call gets dropped. My sense this issue arises when the dropped participant is having bandwidth issues.

Steve

I really like the Skype unlimited plan. You can only use it to make outgoing calls, not take incoming calls to a phone number, and you are restricted to the US (and I think maybe Canada too), but with those caveats it's very useful. There's another Skype service that lets you take incoming calls, but I haven't tried it. Of course, other Skype users can easily contact you from their computers. Skype-to-Skype calling is free across the whole world.

Users of Skype should be aware of the methods to avoid being treated as a supernode by using a suitably configured firewall and/or on Windows machines to upgrade the registry, (not for the feint-hearted).

This link provides a reference base:

https://www.cs.uwaterloo.ca/twiki/view/CF/SkypeConfiguration

Those affected will be publicly available systems without a NAT.

Better alternatives are to use a SIP based system. Skype though popular, remains a P2P VOIP system and the code is not open source.

As long as you have a broadband router between your computer and the internet you don't need to worry about this.

The biggest thing I would worry about on the Skype system, and I use the word worry loosely, is whether or not your online availability is viewable by only your contacts or by everyone. If you don't want to screen the occasional call I would keep it set to only your contacts.

I have my available by everyone and I also have it configured so that you can see my availability right from the support page on my website. If you have Skype you can click on it and call me.

William, why don't you test it out with Brianna?

;]

-Andrey

Hi Brianna, Technogeek here with another alternative: Skype's primary competitor is GizmoProject, I can't remember if I told about that back when we were working on your podcast. Anyway, they just came out with a new release (though only for windows today) that has lots of new features. It's very much worth a checkout: http://www.gizmoproject.com

Cheers, leif

So, what does all that mean in a couple of sentences? You agree to allow Skype to use your computer and connection as part of it's shared network. If you have a fast connection you might end up with the Skype system using your computer over and above what you would wish it to use. Of course it depends on your connection but it is a problem for some people.

The presence of a broadband router does not normally limit incoming requests and so in this matter it is not a useful solution. The need to limit Skype use of your computer as a supernode is of course up to you. I have found the most reliable alternative is to use a SIP based system such as that described.

To be clear, you are at risk. It is important not to be overwhelmed with the technicalities.

I really wouldn't want this thread to degrade into a technical spat (for we are perhaps all correct but from many different viewpoints). You about the use of a Skype product and I really only wanted to highlight the dangers (actually quite realistic) of becoming a Skype supernode. The main problems which occur for personal users are degradation of service due to the high number of TCP connections rather than a reduction of available bandwidth.

As far as recommendation of other VoIP systems I too recommend Gizmo and also urge you to look at anything which uses the SIP protocol rather than a proprietary one.

From Skype's Documentation:

There are several ways to prevent Skype from becoming a supernode:

• Beginning with Skype 3.0, an explicit switch is provided in the registry settings to allow the disabling of supernode functionality.

• Any computer hosted on a network that is behind a network address translation (NAT) device or restrictive firewall will disable supernode functionality.

• Skype clients behind an HTTP or SOCKS5 proxy will not serve as supernodes.

What this means for you or anyone using Skype is that as long as you are behind a Broadband Router / Gateway you will not become a Supernode as indicated earlier.

NAT is a technology that allows the Broadband Router / Gateway to send out traffic from your computer to the internet and directing traffic from the internet to your computer. It does this while adding a layer of protection against direct access to your computer.

The risk described by Chris would only affect computers connected directly to the cable or dsl modem without a Broadband Router / Gateway in between. The only way you could be at risk with a Broadband Router / Gateway is if you put your computer's IP Address in the DMZ.

For more information on all subjects:
Skype Supernodes
DMZ

"NAT is a technology that allows the Broadband Router / Gateway to send out traffic from your computer to the internet and directing traffic from the internet to your computer. It does this while adding a layer of protection against direct access to your computer."

This is almost, not not quite, entirely unlike what NAT actually is.

NAT is not a security featureset, or a routing system. NAT, which stands for Network Address Translation is merely a system to masquerade many unroutable IP addresses behind one or many, and provide for IP Address Mapping. NAT traversal is a rather trivial endeavor, and it's scary to consider NAT as any sort of protection. It's sort of like standing in front of a mugger and saying "I don't really have my wallet, my wife does, therefore you are thwarted" while your wife is standing next to you.

NAT, along with CIDR were developed in the early 1990s to address a foreseen shortage of IP addresses due to poor space allocation practices.

If you'd like a greater understanding of the technologies involved, read these links for more information on RFC1631 (NAT), RFC 1918 (Address Allocation for Private Internets), and http://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing

http://www.faqs.org/rfcs/rfc1631.html http://www.faqs.org/rfcs/rfc1918.html

I used to work with this guy named Frank Beers. Back 11 years ago (or so) when MS Proxy Server 2.0 just rolled off the line he used to pride himself on his home network. Back then the only affordable solution to connect multiple computers to a single routable (internet) IP address was software. You see, DSL was just starting to be available and cable was just starting to pop up as well.

Frank kind of talked in a nasally voice and spouted all day about his prahxsy (how it sounded) server and how he could connect two or more computers through it. Anyway, then the Cable / DSL Routers appeared on the scene. I remember I used a .dll file that ran as a service on my NT 4 box. I don't remember the name of it any longer.

Anyway, the point is that most of you got the gist from my original post on NAT. And if you have a Broadband Router that is less than 5 years old it will usually have a Stateful Packet Inspection firewall built right in. Jeeze, the more terms I throw out the more links I have to provide... So, your risks for having Skype turn you into a supernode are nil if you have a computer connected to a broadband router connected to the internet.

This does not mean that you have the best security that money can buy. You have to patch those computers and keep up to date antivirus on them. It doesn't hurt to keep a software firewall turned on either.

For your reading pleasure:
A less technical, more readable article on NAT
Stateful Packet Inspection

The only flaw I see in the Mugger analogy is that the mugger would actually have to be a super high tech cat burglar because the wife would not actually be directly visible.

However, there is not much the husband can do if the wife lets the cat burglar in through the window in the form of spyware or email viruses.

I like analogies!

Well, Brianna it might indeed look like a can of worms but it is a useful vehicle for a dialogue which might help many users.

Michael's analogy is excellent.

Skype uses a relatively sophisticated method to maintain state or semi-state and p2p protocol (used in KaZaA) successfully enables operation even where both users (to the call) are behind NATs. It does this by hole-punching or reverse connectivity by initiating direct contact with a supernode at startup and later opening multiple TCP/UDP connections. This serves as a routable address. After all, that's how you know when another Skype user is trying to contact you without you initiating the call! Magically, the computer 'rings' to signify an incoming call without you making one! To do that and to increase call quality it prefers to use a NAT/ router which is 'p2p friendly'. Reportedly, over 75% of routers are 'p2p friendly' and permit this traversal. My own investigations last year revealed that most 'home' routers are 'p2p friendly' by default.

Further, Skype is also very helpful by opening all these capabilities for you and updating its own software without intervention by you. As such it is a security risk to some and not to others. I can only speak for myself and say that I could never allow it to exist on any of my systems even though I accept that it is popular. I tested it (in the UK not here in the USA) and quickly became a supernode.

Most system degradation for home users appears to be caused by a flood of connection requests causing delays in your own work. These can be reduced if you shut down your computer periodically, or only start the Skype application when needed...then shutting it down completely when the call is terminated. Certainly, avoid having it start when the computer is switched on as it will run in the background.

The fact remains that Skype continues to be highly popular. Indeed, a few of my colleagues still use it. I see nothing wrong in that because they are only online for a few minutes at a time before closing.

For general use I highly recommend Yahoo Messenger as it also incorprates elementary one-to-one video connectivity. For full, no-cost video-conferencing, use EVO/VRVS. For all other VoIP, I continue to recommend SIP. Cranky old-timers like me prefer two tin-cans and a piece of string...but only when we know we can cut the string after the call! Have fun! Stay aware!

http://www.us-cert.gov/