installation

Start by updating and upgrading your system with the following command.
apt-get update; sudo apt-get upgrade -y

Install the following dependencies with the following command:
sudo apt-get install -y build-essential git-core pkg-config subversion libjansson-dev sqlite autoconf automake libtool libxml2-dev libncurses5-dev unixodbc unixodbc-dev libasound2-dev libogg-dev libvorbis-dev libneon27-dev libsrtp0-dev libspandsp-dev uuid uuid-dev sqlite3 libsqlite3-dev libgnutls-dev libtool-bin python-dev texinfo

Reboot your system so that your system will recognise what was installed, do:
sudo shutdown -r now

Let's install linux header for your system with:
sudo apt-get install wget libssl-dev libncurses5-dev libnewt-dev  libxml2-dev linux-headers-$(uname -r) libsqlite3-dev uuid-dev

Now change directory, to and clone iksemel, configure and it with:
cd /usr/src
git clone git://github.com/meduketto/iksemel
cd iksemel
./autogen.sh
./configure
make && make install


Get dahdi and install it with:
cd /usr/src
wget http://downloads.asterisk.org/pub/telephony/dahdi-linux-complete/dahdi-linux-complete-current.tar.gz
tar xvfz dahdi-linux-complete-current.tar.gz
cd dahdi-linux-complete-*
make all && make install && make config

 ./contrib/scripts/install_prereq install
./contrib/scripts/install_prereq install-unpackaged

Time to install libpri with:
cd /usr/src
wget http://downloads.asterisk.org/pub/telephony/libpri/libpri-1.4-current.tar.gz
tar xvfz libpri-1.4-current.tar.gz
cd libpri-*
make && make install

Now install the asterisk from git with:
cd /usr/src/
git clone https://github.com/asterisk/pjproject.git
cd pjproject
./configure --enable-shared --disable-sound --disable-resample --disable-video --disable-opencore-amr
make dep && make && make install

Just in case, you might want to install these:
sudp apt-get install mpg123 libmpg123-0 sox openssl subversion openssh-server 

Let's get sound into asterisk directory with:
cd /var/lib/asterisk/sounds
wget http://downloads.asterisk.org/pub/telephony/sounds/asterisk-core-sounds-en-wav-current.tar.gz
wget http://downloads.asterisk.org/pub/telephony/sounds/asterisk-extra-sounds-en-wav-current.tar.gz
tar xvf asterisk-core-sounds-en-wav-current.tar.gz
rm -f asterisk-core-sounds-en-wav-current.tar.gz
tar xfz asterisk-extra-sounds-en-wav-current.tar.gz
rm -f asterisk-extra-sounds-en-wav-current.tar.gz

# Don't forget the Wideband Audio download
wget http://downloads.asterisk.org/pub/telephony/sounds/asterisk-core-sounds-en-g722-current.tar.gz
wget http://downloads.asterisk.org/pub/telephony/sounds/asterisk-extra-sounds-en-g722-current.tar.gz
tar xfz asterisk-extra-sounds-en-g722-current.tar.gz
rm -f asterisk-extra-sounds-en-g722-current.tar.gz
tar xfz asterisk-core-sounds-en-g722-current.tar.gz
rm -f asterisk-core-sounds-en-g722-current.tar.gz

And we're done!