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SIP vs. Skype, Making the "Open" Choice
techie34290 writes "If you were to make the choice between SIP and Skype for Linux, which one would you go for? Matt Hartley from MadPenguin.org says to opt for SIP. Why? "One tidbit of information that most people are not likely aware of is that when you install the Skype client, it will drain system resources by running as a supernode from time to time. Granted, this is not always the case; however, the very idea of my PC having its resources tied up for someone else's phone call is frankly maddening to me."
the very idea of my PC having its resources tied up for someone else's phone call is frankly maddening to me
This strikes me as an attitude of someone who can't stand the idea that he's not in control of everything (which you never are). The real question is, does it use any significant resources that effect what you're trying to do at the time? Frankly I don't really care about 20-50 megabytes of memory, or 5% of my processor usage, or even 100% of my idle processor usage. Those numbers are all low enough that you'd more than likely never notice or miss those resources. I would be concerned if the app started taking up hundreds of megabytes of memory, or 30-40% of my processor time, or locked up system resources that interfere with other apps I'm running. So which is it? The author didn't provide us with any of that information, only the extremist position that ANY useage of his computers resources that wasn't for him was unacceptable. What a useless article.
AccountKiller
Yes!
Sip plays merry hell with firewalls. Don't even think about it unless you've got a VPN back to your sip server! If you have then it works great. The new Nokia E70 phone connects to our office Asterisk server via SIP and works very well ( http://europe.nokia.com/phones/e70 ).
IAX2 goes through NATed firewalled links just fine. It is much easier to configure if you are on the move (or your users are).
I wouldn't touch Skype with the proverbial barge pole given its closed nature.
Every man for himself, all in favour say "I"
He'd prefer that the supernode feature be removed entirely and Skype calls only ever consume the resources of the consenting parties directly involved in it.
Skype is a black hole. Sure I could open it up in my firewall but why would I? As I understand it skype could easily use a couple of gigs of bandwidth every month with no way to control it or even measure the usage. I could probably set up a couple of QOS rule to tame it down but that would take time, and the only benifit I would get is letting an unknown protocol connect to my home computer through a closed source app.
I'm also sick and tired of installing all these proprietary apps, each with it's own protocol and from the looks of it every couple of years there is the next big thing you need to install. Not because it's actully better but because someone you need to write/talk to has it. No thanks, we need something open and documented. Then every company could make their own client, brand it, sell it and popup commercials all day long as they wish. And I could use something smaller OSS that suits my needs.
And I would gladly contribute both bandwidth and cpu usage. But never for skype as it stands now.
Actually, the only reason this is done is that, for two computers without the ability to open up a listening port to Internet, they have trouble contacting one another. So, Skype uses one of its members as a through-way for a call. Calls done in this manner are reduced in quality to reduce the third-party's overhead (since you're essentially leeching off another human to do it).
It would be very nice to find a way to make a TCP/IP connection without having a listening port. I believe it could be done, still using the third party for setting up the connection, but using a spoof of some nature.
A possible way is: Caller (C) requests a connection via the Skype Network (SN) to Reciever (R). R is connected to SN, but has no incoming connection capabilities, so SN requests a transitional connection from a third party (T). C and R both call T. R tells T which local port its connection is on. T spoofs C, telling C that its IP address and port are those of T. T also spoofs R, telling it that its IP address is that of C, connecting on R's port(R effectively becomes the server, the router's outgoing port becoming the incoming port). R and C, knowing this will happen, do all the syn/ack stuff manually.
I'm not well enough versed in TCP/IP to do this (or even say whether it can be done), but perhaps someone is.
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I can confirm that this is occuring. I work at a University, and while they do not, technically, ban Skype outright, they might as well. The reason for this is that Skype likes to put computers on our network into supernode mode (considering the bandwidth here, I understand why it happens). The problem is that it starts eating bandwidth like mad, and reduces bandwidth available for other users. So, in order to combat the bandwidth hogging, Skype traffic is throttled at the firewall; it is still allowed to connect and use some bandwidth, but you can forget video conferencing. And before I get any of the "but, but, but...student's rights" type posts: we are a private university, i.e. no public funds; the students have the right to go elsewhere if they don't like it.
Actually, this is a rather timely article, as I am working on setting up a video conferencing room and need to find good free/cheap options.
Necessity is the mother of invention.
Laziness is the father.