I haven't used or built Freeswitch yet, but I'm getting closer to that point. I will be building from source. Having looked at the documentation I can see that Debian is preferred, and the use of distros in general. However, I don't use distros, but rather build my own systems from scratch. I've looked at the Centos page ( https://freeswitch.org/ confluence/display/FREESWITCH/CentOS+7+and+RHEL+7 ) and under "Building from source" there appears to be a list of dependencies. I already have most of those dependencies installed (other than the codecs) but I have three questions which maybe somebody can answer. The first is: can openssl be substituted with libressl, which I use? The second is: "mongo-c-driver-devel" suggests that mongodb is a dependency of Freeswitch. I've seen no mention of mongodb anywhere in either the book, or the documentation generally, so why is this listed as a dependency? The third is: there is no mention of package version numbers anywhere, so how can I find if there are any issues with particular versions? Any help gratefully received. -- Richard Melville Systems Architect cellularity.co.uk stellarsystem.wordpress.com +44 20 33 555 305 +44 7957 836330