$(dd if=/dev/zero of=$test_file bs=$(echo "$test_size*1024" | bc) count=1 &> /dev/null)

    # upload test
    # echo "Testing upload to $ssh_server..."
    up_speed="$(scp -v $test_file $ssh_server:$test_file 2>&1 | grep "Bytes per second" | sed "s/^[^0-9]*\([0-9.]*\)[^0-9]*\([0-9.]*\).*$/\1/g")"
    up_speed="$(echo "($up_speed*0.0009765625*100.0+0.5)/1*0.01" | bc)"

    # download test
    # echo "Testing download to $ssh_server..."
    down_speed="$(scp -v $ssh_server:$test_file $test_file 2>&1 | grep "Bytes per second" | sed "s/^[^0-9]*\([0-9.]*\)[^0-9]*\([0-9.]*\).*$/\2/g")"
    down_speed="$(echo "($down_speed*0.0009765625*100.0+0.5)/1*0.01" | bc)"

    # clean up
    # echo "Removing test file on $ssh_server..."
    $(ssh $ssh_server "rm $test_file")
    # echo "Removing test file locally..."
    $(rm $test_file)