diff --git a/prometheus_ss_exporter/selection.py b/prometheus_ss_exporter/selection.py
index 19dd714..4c5e16d 100644
--- a/prometheus_ss_exporter/selection.py
+++ b/prometheus_ss_exporter/selection.py
@@ -6,11 +6,14 @@
 class Selector:
     class Discerner:
         def ports(self, flow, portranges):
+            if not portranges:
+                return True
+
             for p_range in portranges:
-                if ((flow['dst_port'] < p_range['lower']) or
-                   (flow['dst_port'] > p_range['upper'])):
-                    return False
-            return True
+                if ((flow['dst_port'] >= p_range['lower']) and
+                   (flow['dst_port'] <= p_range['upper'])):
+                    return True
+            return False
 
         def peers(self, flow,
                   hosts=[], addresses=[], networks=[]):
@@ -41,10 +44,11 @@ def process(self, flow,
                     pids=[], cmds=[]):
             flow_pids = []
             flow_cmds = []
-            for usr, pid_ctxt in flow['usr_ctxt'].items():
-                for pid, cmd_ctxt in pid_ctxt.items():
-                    flow_pids.append(pid)
-                    flow_cmds.append(cmd_ctxt['full_cmd'])
+            if flow.get('usr_ctxt'):
+                for usr, pid_ctxt in flow['usr_ctxt'].items():
+                    for pid, cmd_ctxt in pid_ctxt.items():
+                        flow_pids.append(pid)
+                        flow_cmds.append(cmd_ctxt['full_cmd'])
 
             for pid in pids:
                 if pid in flow_pids:
@@ -71,16 +75,15 @@ def arbitrate(self, flow):
         return self._core(flow)
 
     def _arbitrate(self, flow):
-        conditions = [self.discern.ports(flow, self.cnfg['peering']['portranges']),
-                      self.discern.peers(flow,
-                                         hosts=self.cnfg['peering']['nodes']['hosts'],
-                                         addresses=self.cnfg['peering']['nodes']['addresses'],
-                                         networks=self.cnfg['peering']['nodes']['networks']),
-                      self.discern.process(flow,
-                                           pids=self.cnfg['process']['pids'],
-                                           cmds=self.cnfg['process']['cmds'])
+        conditions = [ self.discern.ports(flow, self.cnfg.get('peering').get('portranges')) if self.cnfg.get('peering') else True,
+                       self.discern.peers(flow, hosts=self.cnfg.get('peering').get('hosts'),
+                                                addresses=self.cnfg.get('peering').get('addresses'),
+                                                networks=self.cnfg.get('peering').get('networks')) if self.cnfg.get('peering') else True,
+                       self.discern.process(flow, pids=self.cnfg.get('process').get('pids'),
+                                                  cmds=self.cnfg.get('process').get('cmds')) if self.cnfg.get('process') else True
                       ]
-        if it.dropwhile(lambda _: _, conditions):
-            return True
+        # if one condition false, we decline sample
+        if list(it.filterfalse(lambda _: _, conditions)):
+            return False
 
-        return False
+        return True
diff --git a/test/selection_test.py b/test/selection_test.py
index 69e16a0..a5aeded 100644
--- a/test/selection_test.py
+++ b/test/selection_test.py
@@ -8,6 +8,7 @@ class SelectorTesting(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
         cls.discerner = selection.Selector.Discerner()
+        cls.selector = selection.Selector
 
     def test_peers_decline(self):
         selector_addr = ["10.0.1.10"]
@@ -94,3 +95,35 @@ def test_process_accept_test(self):
         outcome = SelectorTesting.discerner.process(flow,
                                                     cmds=selector_cmds)
         self.assertTrue(outcome)
+
+    def test_combined_accept_test(self):
+        selection_config = {
+                'selection': {
+                    'peering': {
+                        'networks': [ '192.168.0.0/16' ],
+                        'portranges': [{ 'lower': 1000, 'upper': 2000 }]
+                        }
+                    }
+                }
+        flow = {'dst': '192.168.92.41', 'dst_port': 1500}
+
+        selector = SelectorTesting.selector(selection_config)
+        outcome = selector.arbitrate(flow)
+
+        self.assertTrue(outcome)
+
+    def test_combined_decline_test(self):
+        selection_config = {
+                'selection': {
+                    'peering': {
+                        'networks': [ '192.168.0.0/16' ],
+                        'portranges': [{ 'lower': 1000, 'upper': 2000 }]
+                        }
+                    }
+                }
+        flow = {'dst': '192.168.92.41', 'dst_port': 900}
+
+        selector = SelectorTesting.selector(selection_config)
+        outcome = selector.arbitrate(flow)
+
+        self.assertFalse(outcome)