Other SIP Proxies

Other SIP Proxies

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Transcript

[slide531] We mentioned Jane yesterday, SIPdroid. There's even Yxa, which is a SIP server written in Erlang. Now, why would you want a SIP server written in Erlang? OK, anyone know what Erlang is? Right? So what's Erlang? [student answers: Erlang is a language, but it has the OTP server, which is very powerful, that it can spawn a lot of microprocessing. It's really good on the email level connection.] And in particular, one of the cool features of Erlang is that I can release new releases of software while the system is running. And the old users of the old software keep using the old software. The new versions will start using the new software. And when the last users of the old software stop, what happens? It gets garbage collected away. So it's a very, very cool language that was developed by a set of researchers at Ericsson. And it was designed so you don't have this idea, oh, I have to stop and reboot to install the new software. No, you can't say for your public switch or something like that, we're sorry, we have to reboot for a few minutes. You won't be able to have any calls or anything until we reboot it. No, it needs to stay up. And they have had a number of spin-out companies from that effort because the former CEO basically got upset because it was being used in too many projects. And they got worried, saying, oops, if all of these projects are all using this, where can we get all these Erlang programmers? They're only available here in Sweden. Oops, that's a bad idea. So what happened? They shut down all the new projects in Erlang. And many of those people said, fine, sayonara. And they went and they formed other companies like Blue Tail and others. And they produced some of the highest performance database systems that are commercially available by taking this technology that they had So what's the time to spin up a new thread? Like 50 microseconds or something like that? Just blazingly fast in comparison to the cost of instantiating a new VM to have a new server for something. So it makes for some interesting tools.