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On Kamailio World 2018, part II

In the first part of my brain dump about this year's edition of Kamailio World I focused mainly on testing. Core developers and application designers want to be able to test the behaviour of Kamailio-based architectures with minimal effort and fast feedback.

A different dimension to testing, that I haven't mentioned in my previous post, was related to Fuzz testing. There were two presentations focused on this: Sandro Gauci's (The easiest way to understand who Sandro is: listen on port 5060 on the public Internet and wait a couple of minutes. You'll see a SIP request from a tool called sipvicious (aka friendly-scanner), a penetration testing tool Sandro wrote (and others misuse)) and Henning Westerholt, historical member of the Kamailio community.

Sandro's presentation focused around fuzzing approaches for RTC in general (slides), while Henning was more specifically focused on Kamailio.

Fuzzing is a sophisticated technique to verify the robustness of a software application, by sending input that can vary greatly from the typical or expected usage. The objective is to find weaknesses that can lead to crashes or other malfunctions, so that they can be fixed. Of course testing a server like Kamailio is even trickier than testing an application that can read from a file. It is a fascinating topic.

Kamailio proved to be very robust: Henning reported an average of  about 1 message every 44 million required to make Kamailio misbehave. The video of Henning's presentation is here (by the way, Pascom have done a great work this year too, providing a flawless video streaming and recording. It feels like we are a little spoiled, because we give it for granted and barely notice all the work behind it).

In terms of learning opportunities for architects and administrators of Kamailio-based infrastructure, I found very valuable Daniel's presentations around high-level scripting (with KEMI) to build the routing logic (Video and slides).

Remember that Lua may not be the most popular - apparently - but it's the one estimated to give you performances closest to the native routing language.

Another valuable presentation was around the Least Cost Routing techniques that the Kamailio environment makes available. (Video, and slides). Some solutions use out of the box modules (like lcr, carrierroute, drouting), some are more indirect (pdt, mtree, dialplan, prefix_route), and others are a combination of them. Must-see if you're working in that area.

Another learning goldmine has been Lorenzo Miniero's (author of Janus, a WebRTC conferencing framework (this definition is mine)) lecture about Privacy, Security and Authentication for WebRTC. (Video and slides) Lorenzo does talk fast, but no word is spoken in vain. Worst case, you can watch the video at 0.5 speed (smile). Interesting the case of double encryption for media.



I guess there's enough for a part III in the near future! To be continued. 

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