Janus is an open source, general purpose, WebRTC gateway designed and developed by Meetecho. This version of the gateway can only be installed on Linux systems: next versions will take into account cross compilation on different environments.

For some online demos and documentations, make sure you pay the project website a visit!

To discuss Janus with us and other users, there's a Google Group called meetecho-janus that you can use. If you encounter issues, though, please submit an issue on github instead.

##Dependencies To install it, you'll need to satisfy the following dependencies:

• libmicrohttpd
• libini-config (INI configurations)
• Jansson
• libnice
• OpenSSL (at least v1.0.1e)
• libsrtp
• Sofia-SIP
• usrsctp (only needed if you are interested in Data Channels)
• libwebsock (only needed if you are interested in WebSockets support)

A couple of plugins depend on a few more libraries:

• libopus (only needed for the bridge plugin)
• libogg (only needed for the voicemail plugin)

Additionally, you'll need the following libraries and tools:

• GLib
• pkg-config
• gengetopt

All of those libraries are usually available on most of the most common distributions. Installing these libraries on a recent Fedora, for instance, is very simple:

yum install libmicrohttpd-devel jansson-devel libnice-devel \
   openssl-devel libsrtp-devel sofia-sip-devel glib-devel \
   opus-devel libogg-devel libini_config-devel pkg-config gengetopt

On Ubuntu or Debian, it would require something like this:

aptitude install libmicrohttpd-dev libjansson-dev libnice-dev \
	libssl-dev libsrtp-dev libsofia-sip-ua-dev libglib2.0-dev \
	libopus-dev libogg-dev libini-config-dev libcollection-dev \
	pkg-config gengetopt

• Note: please notice that libopus may not be available out of the box on Ubuntu or Debian, unless you're using a recent version (e.g., Ubuntu 14.04 LTS). In that case, you'll have to install it manually.

For what concerns usrsctp, which is needed for Data Channels support, it is usually not available in repositories, so if you're interested in them (support is optional) you'll have to install it manually. It is a pretty easy and standard process:

svn co http://sctp-refimpl.googlecode.com/svn/trunk/KERN/usrsctp usrsctp
cd usrsctp
./bootstrap
./configure --prefix=/usr && make && sudo make install

• Note: you may need to pass --libdir=/usr/lib64 to the configure script if you're installing on a x86_64 distribution.

The same applies for libwebsock, which is needed for the optional WebSockets support. If you're interested in supporting WebSockets to control Janus, as an alternative (or replacement) to the default plain HTTP REST API, you'll have to install the version 1.0.4 manually:

wget http://paydensutherland.com/libwebsock-1.0.4.tar.gz
tar xfv libwebsock-1.0.4.tar.gz
cd libwebsock-1.0.4
./configure --prefix=/usr && make && sudo make install

• Note: you may need to pass --libdir=/usr/lib64 to the configure script if you're installing on a x86_64 distribution.

Please notice that you have to install version 1.0.4 and not any later version. In fact, recent versions of libwebsock added support for threading in the library, but it is currently experimental and doesn't work as expected in Janus.

Should you be interested in building the gateway documentation as well, you'll need an additional component installed too:

• Doxygen
• Graphviz

On Fedora:

yum install doxygen graphviz

On Ubuntu/Debian:

aptitude install doxygen graphviz

##Compile Once you have installed all the dependencies, just use:

sh install.sh

to start the whole compilation process. If you're not interested in Data Channels or WebSockets (or you don't care about either of them) you can pass a specific compilation flag to disable them:

sh install.sh nodatachans nowebsockets

As the flag names suggest, 'nodatachans' disables support for Data Channels, while 'nowebsockets' disables WebSockets.

The script will then try to check whether you have all the dependencies installed, and then issue a 'make' for you to start compiling. If Doxygen and graphviz are available, it will also build the documentation for you as well in the docs/html subfolder. If you prefer not to build the documentation (or not to build it again and again every time you compile!) use the 'nodocs' option (along 'nodatachans' and 'nowebsockets', if needed):

sh install.sh nodocs

##Configure and start To start the gateway, you can use the janus executable. There are several things you can configure, either in a configuration file:

./conf/janus.cfg

or on the command line:

./janus --help

janus 0.0.4

Usage: janus [OPTIONS]...

-h, --help                    Print help and exit
-V, --version                 Print version and exit
-i, --interface=ipaddress     Interface to use (will be the public IP)
-p, --port=portnumber         Web server HTTP port (default=8088)
-s, --secure-port=portnumber  Web server HTTPS port (default=no HTTPS)
-n, --no-http                 Disable insecure HTTP web server  (default=off)
-b, --base-path=basepath      Base path to bind to in the web server 
							  (default=/janus) 
-w, --ws-port=portnumber      WebSockets server port (default=no WebSockets)
-W, --ws-secure-port=portnumber
                              Secure WebSockets server port (default=no 
                              secure WebSockets)
-N, --no-websockets           Disable insecure WebSockets server  
                              (default=off)
-P, --plugins-folder=path     Plugins folder (default=./plugins)
-C, --config=filename         Configuration file to use
-F, --configs-folder=path     Configuration files folder (default=./conf)
-c, --cert-pem=filename       HTTPS/DTLS certificate
-k, --cert-key=filename       HTTPS/DTLS certificate key
-S, --stun-server=filename    STUN server(:port) to use, if needed (e.g., 
							  gateway behind NAT, default=none)
-X, --ice-ignore-list=list    Comma-separated list of interfaces or IP 
                              addresses to ignore for ICE gathering; 
                              partial strings are supported (e.g., 
                              vmnet8,192.168.0.1,10.0.0.1 or 
                              vmnet,192.168., default=vmnet)
-e, --public-ip=ipaddress     Public address of the machine, to use in SDP
-r, --rtp-port-range=min-max  Port range to use for RTP/RTCP (only available
							  if the installed libnice supports it)
-d, --debug-level=1-7         Debug/logging level (0=disable debugging, 
                              7=maximum debug level; default=4)
-a, --apisecret=randomstring  API secret all requests need to pass in order 
                              to be accepted by Janus (useful when wrapping 
                              Janus API requests in a server, none by 
                              default)

Options passed through the command line have the precedence on those specified in the configuration file. To start the gateway, simply run:

./janus

This will start the gateway, and have it look at the configuration file. By default, only an HTTP webserver is started. To enable HTTPS support, edit the configuration file accordingly or use the command line. The webserver will make use of the same certificates provided for DTLS. You can also change the base path that the webserver uses: by default this is /janus, but you can change it to anything you want and with any nesting you want (e.g., /mypath, /my/path, or /my/really/nested/path). This is done to allow you to more easily customize rules in any frontend you may have (e.g., Apache in front of your services). Please notice that the path configuration has no effect on the WebSockets usage of the API, instead, as it is not needed there.

In the absence of a configuration file, the only mandatory options to specify in the command line are the ones related to the DTLS certificate. A default certificate is provided with this package in the certs folder, which you can use launching the executable with these parameters:

./janus -c certs/mycert.pem -k certs/mycert.key

At this point, the gateway will be listening on the 8088 port (or whatever you changed that to) of your machine. To test whether it's working correctly, you can use the demos provided with this package in the html folder: these are exactly the same demos available online on the project website. Just copy the file it contains in a webserver, and open the index.html page in either Chrome or Firefox. A list of demo pages exploiting the different plugins will be available.

##Help us! Any thought, feedback or (hopefully not!) insult is welcome!

Developed by @meetecho