diff --git a/lib/puppet/type/network_route.rb b/lib/puppet/type/network_route.rb
index 605beed6..79997936 100644
--- a/lib/puppet/type/network_route.rb
+++ b/lib/puppet/type/network_route.rb
@@ -46,7 +46,7 @@
       desc:      'scope of the destinations covered by the route prefix.',
     },
     protocol: {
-      type:      'String',
+      type:      'Enum["static", "redirect", "kernel", "boot", "ra"]',
       desc:      'routing protocol identifier of this route.',
       default:   'static',
     },
diff --git a/spec/unit/puppet/type/network_route_spec.rb b/spec/unit/puppet/type/network_route_spec.rb
index 29a7bb8e..41438fd2 100644
--- a/spec/unit/puppet/type/network_route_spec.rb
+++ b/spec/unit/puppet/type/network_route_spec.rb
@@ -5,4 +5,164 @@
   it 'loads' do
     expect(Puppet::Type.type(:network_route)).not_to be_nil
   end
+
+  context 'prefix is default' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        default_route: true,
+      )
+    end
+
+    it 'prefix is set' do
+      expect(resource[:prefix]).to eq 'default'
+    end
+
+    it 'name is set to prefix' do
+      expect(resource[:name]).to eq 'default'
+    end
+
+    it 'default_route should be true' do
+      expect(resource[:default_route]).to eq :true
+    end
+
+    it 'metric should be 100' do
+      expect(resource[:metric]).to eq '100'
+    end
+
+    it 'protocol should be static' do
+      expect(resource[:protocol]).to eq 'static'
+    end
+  end
+
+  context 'with a non-default route' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: '10.155.255.0/24',
+        default_route: false,
+        metric: '600',
+        source: '10.155.255.110'
+      )
+    end
+
+    it 'prefix is set to network address' do
+      expect(resource[:prefix]).to eq '10.155.255.0/24'
+    end
+
+    it 'default_route is false' do
+      expect(resource[:default_route]).to eq :false
+    end
+
+    it 'metric is set to 600' do
+      expect(resource[:metric]).to eq '600'
+    end
+
+    it 'source is set to 10.155.255.110' do
+      expect(resource[:source]).to eq '10.155.255.110'
+    end
+  end
+
+  context 'with gateway set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        gateway: '10.155.255.1'
+      )
+    end
+
+    it 'gateway should be 10.155.255.1' do
+      expect(resource[:gateway]).to eq '10.155.255.1'
+    end
+  end
+
+  context 'with interface set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        interface: 'eth0'
+      )
+    end
+
+    it 'interface should be eth0' do
+      expect(resource[:interface]).to eq 'eth0'
+    end
+  end
+
+  context 'with metric set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        metric: '400'
+      )
+    end
+
+    it 'metric should be 400' do
+      expect(resource[:metric]).to eq '400'
+    end
+  end
+
+  context 'with table set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        table: 'main'
+      )
+    end
+
+    it 'table should be main' do
+      expect(resource[:table]).to eq 'main'
+    end
+  end
+
+  context 'with source set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        source: '10.155.255.10'
+      )
+    end
+
+    it 'source should be 10.155.255.10' do
+      expect(resource[:source]).to eq '10.155.255.10'
+    end
+  end
+
+  context 'with scope set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        scope: 'link'
+      )
+    end
+
+    it 'scope should be link' do
+      expect(resource[:scope]).to eq 'link'
+    end
+  end
+
+  context 'with protocol set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        protocol: 'boot'
+      )
+    end
+
+    it 'protocol should be boot' do
+      expect(resource[:protocol]).to eq 'boot'
+    end
+  end
+
+  context 'with mtu set' do
+    let(:resource) do
+      Puppet::Type.type('network_route').new(
+        prefix: 'default',
+        mtu: '1500'
+      )
+    end
+
+    it 'mtu should be 1500' do
+      expect(resource[:mtu]).to eq '1500'
+    end
+  end
 end