skype...Geluid

Een stuk uit een podcast over skype, en waar mee je de verbinding. (het geluid) aanzienlijk mee verbetert, kunt verbeteren door een kleine ingreep in de instellingen.

Leo: So, again, because it has a third-party server. I thought you were going to reveal our secret, which I don’t want anybody to know, about how we get these Skype calls to sound so good, which is that we use a dedicated Skype port. You told me to do this, and I have to say it has improved the quality of the Skype calls. Why?

Steve: Well, because I’ve configured my Skype so that I’m able to – I have basically, of course, a non-default random port where incoming Skype connections are able to reach me.

Leo: You can do that in the Skype preferences. It’s in the advanced preferences. It’s easy to...

Steve: Yes. And the reason – I have a NAT-hostile network configuration. As you can imagine, Leo, my security here is pretty strong. And you and I, when we were connecting, were not able to get a direct connection because my NAT router wouldn’t allow it. So that our dialogue was going through a so-called “supernode.” It was being relayed by a third party. And when you were telling me that you and I were having such great success with Skype but you were having some trouble with other uses of Skype when you were talking to people, that’s when I suggested, well, if you did the same thing, if you allowed a fixed port to come all the way in from the Internet to your Skype, then basically, you know, if you – then it’s like you’re only behind a single NAT router. That is, the person you’re connecting to is only behind a single NAT router. They are always able to initiate a connection through to you, so a supernode is never used, and you get this kind of Skype quality every time.

Leo: The supernodes are a clever hack that the Skype folks did so that you don’t have router problems, NAT router problems. But you can avoid it by using a dedicated port. Now, I do that unilaterally, right, I don’t have to tell them what port I’m using. I just choose a dedicated port in my connection options.

Steve: Exactly. And suddenly you’re just a higher quality Skype connector location.

Leo: Do I have to open that port in my router or anything like that?

Steve: Yes, you have – yes, yes, yes. You do need to have that port mapped through so that somebody – the idea is that, if both people at each end of a Skype conversation are behind NAT routers, then they may not be able to negotiate to connect to each other directly on the fly, for complex reasons of the way NAT works. But if either of the people will create a statically mapped port through their NAT router, then the other person can always send a packet directly to that port, and the whole Skype protocol manages making sure that everyone knows what the port is.

Leo: Heh heh heh.

Steve: It works.