diff --git a/src/runtime/mod.rs b/src/runtime/mod.rs
index b089a69e4a8f084681e49dbd1438dc383614e707..4dfb9af6d3a5b20a47842fefa838eac1b1f8679d 100644
--- a/src/runtime/mod.rs
+++ b/src/runtime/mod.rs
@@ -29,10 +29,14 @@ pub struct VecLogger(ConnectorId, Vec<u8>);
 pub struct DummyLogger;
 #[derive(Debug)]
 pub struct FileLogger(ConnectorId, std::fs::File);
+#[derive(Debug)]
+struct CurrentState {
+    port_info: HashMap<PortId, PortInfo>,
+    id_manager: IdManager,
+}
 pub(crate) struct NonsyncProtoContext<'a> {
     cu_inner: &'a mut ConnectorUnphasedInner, // persists between rounds
-    proto_component_ports: &'a mut HashSet<PortId>, // sub-structure of component
-    unrun_components: &'a mut Vec<(ComponentId, ProtoComponent)>, // lives for Nonsync phase
+    unrun_components: &'a mut Vec<(ComponentId, ComponentState)>, // lives for Nonsync phase
     proto_component_id: ComponentId,          // KEY in id->component map
 }
 pub(crate) struct SyncProtoContext<'a> {
@@ -66,7 +70,7 @@ struct VecSet<T: std::cmp::Ord> {
 }
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash, serde::Serialize, serde::Deserialize)]
 enum Route {
-    LocalComponent(ComponentId),
+    LocalComponent,
     NetEndpoint { index: usize },
     UdpEndpoint { index: usize },
 }
@@ -79,6 +83,7 @@ enum SubtreeId {
 struct MyPortInfo {
     polarity: Polarity,
     port: PortId,
+    owner: ComponentId,
 }
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 enum Decision {
@@ -102,9 +107,9 @@ enum SetupMsg {
 #[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
 struct SessionInfo {
     serde_proto_description: SerdeProtocolDescription,
-    port_info: PortInfo,
+    port_info: HashMap<PortId, PortInfo>,
     endpoint_incoming_to_getter: Vec<PortId>,
-    proto_components: HashMap<ComponentId, ProtoComponent>,
+    proto_components: HashMap<ComponentId, ComponentState>,
 }
 #[derive(Debug, Clone)]
 struct SerdeProtocolDescription(Arc<ProtocolDescription>);
@@ -140,11 +145,6 @@ struct NetEndpoint {
     inbox: Vec<u8>,
     stream: TcpStream,
 }
-#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
-struct ProtoComponent {
-    state: ComponentState,
-    ports: HashSet<PortId>,
-}
 #[derive(Debug, Clone)]
 struct NetEndpointSetup {
     getter_for_incoming: PortId,
@@ -207,13 +207,14 @@ struct EndpointStore<T> {
     endpoint_exts: Vec<T>,
     polled_undrained: VecSet<usize>,
 }
-#[derive(Clone, Debug, Default, serde::Serialize, serde::Deserialize)]
+#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
 struct PortInfo {
-    owners: HashMap<PortId, ComponentId>,
-    polarities: HashMap<PortId, Polarity>,
-    peers: HashMap<PortId, PortId>,
-    routes: HashMap<PortId, Route>,
+    owner: ComponentId,
+    peer: Option<PortId>,
+    polarity: Polarity,
+    route: Route,
 }
+
 #[derive(Debug)]
 struct ConnectorCommunication {
     round_index: usize,
@@ -225,15 +226,13 @@ struct ConnectorCommunication {
 #[derive(Debug)]
 struct ConnectorUnphased {
     proto_description: Arc<ProtocolDescription>,
-    proto_components: HashMap<ComponentId, ProtoComponent>,
+    proto_components: HashMap<ComponentId, ComponentState>,
     inner: ConnectorUnphasedInner,
 }
 #[derive(Debug)]
 struct ConnectorUnphasedInner {
     logger: Box<dyn Logger>,
-    id_manager: IdManager,
-    native_ports: HashSet<PortId>,
-    port_info: PortInfo,
+    current_state: CurrentState,
     native_component_id: ComponentId,
 }
 #[derive(Debug)]
@@ -325,11 +324,12 @@ impl<T: std::cmp::Ord> VecSet<T> {
         self.vec.pop()
     }
 }
-impl PortInfo {
+impl CurrentState {
     fn spec_var_for(&self, port: PortId) -> SpecVar {
-        SpecVar(match self.polarities.get(&port).unwrap() {
+        let info = self.port_info.get(&port).unwrap();
+        SpecVar(match info.polarity {
             Getter => port,
-            Putter => *self.peers.get(&port).unwrap(),
+            Putter => info.peer.unwrap(),
         })
     }
 }
@@ -403,17 +403,26 @@ impl Connector {
     pub fn new_port_pair(&mut self) -> [PortId; 2] {
         let cu = &mut self.unphased;
         // adds two new associated ports, related to each other, and exposed to the native
-        let [o, i] = [cu.inner.id_manager.new_port_id(), cu.inner.id_manager.new_port_id()];
-        cu.inner.native_ports.insert(o);
-        cu.inner.native_ports.insert(i);
-        // {polarity, peer, route} known. {} unknown.
-        cu.inner.port_info.polarities.insert(o, Putter);
-        cu.inner.port_info.polarities.insert(i, Getter);
-        cu.inner.port_info.peers.insert(o, i);
-        cu.inner.port_info.peers.insert(i, o);
-        let route = Route::LocalComponent(cu.inner.native_component_id);
-        cu.inner.port_info.routes.insert(o, route);
-        cu.inner.port_info.routes.insert(i, route);
+        let mut new_cid = || cu.inner.current_state.id_manager.new_port_id();
+        let [o, i] = [new_cid(), new_cid()];
+        cu.inner.current_state.port_info.insert(
+            o,
+            PortInfo {
+                route: Route::LocalComponent,
+                peer: Some(i),
+                owner: cu.inner.native_component_id,
+                polarity: Putter,
+            },
+        );
+        cu.inner.current_state.port_info.insert(
+            i,
+            PortInfo {
+                route: Route::LocalComponent,
+                peer: Some(o),
+                owner: cu.inner.native_component_id,
+                polarity: Getter,
+            },
+        );
         log!(cu.inner.logger, "Added port pair (out->in) {:?} -> {:?}", o, i);
         [o, i]
     }
@@ -426,32 +435,30 @@ impl Connector {
         use AddComponentError as Ace;
         // 1. check if this is OK
         let cu = &mut self.unphased;
-        let polarities = cu.proto_description.component_polarities(identifier)?;
-        if polarities.len() != ports.len() {
-            return Err(Ace::WrongNumberOfParamaters { expected: polarities.len() });
+        let expected_polarities = cu.proto_description.component_polarities(identifier)?;
+        if expected_polarities.len() != ports.len() {
+            return Err(Ace::WrongNumberOfParamaters { expected: expected_polarities.len() });
         }
-        for (&expected_polarity, port) in polarities.iter().zip(ports.iter()) {
-            if !cu.inner.native_ports.contains(port) {
-                return Err(Ace::UnknownPort(*port));
+        for (&expected_polarity, &port) in expected_polarities.iter().zip(ports.iter()) {
+            let info = cu.inner.current_state.port_info.get(&port).ok_or(Ace::UnknownPort(port))?;
+            if info.owner != cu.inner.native_component_id {
+                return Err(Ace::UnknownPort(port));
             }
-            if expected_polarity != *cu.inner.port_info.polarities.get(port).unwrap() {
-                return Err(Ace::WrongPortPolarity { port: *port, expected_polarity });
+            if info.polarity != expected_polarity {
+                return Err(Ace::WrongPortPolarity { port, expected_polarity });
             }
         }
-        // 3. remove ports from old component & update port->route
-        let new_cid = cu.inner.id_manager.new_component_id();
+        // 2. add new component
+        let new_cid = cu.inner.current_state.id_manager.new_component_id();
+        cu.proto_components
+            .insert(new_cid, cu.proto_description.new_main_component(identifier, ports));
+        // 3. update port ownership
         for port in ports.iter() {
-            cu.inner.port_info.routes.insert(*port, Route::LocalComponent(new_cid));
+            match cu.inner.current_state.port_info.get_mut(port) {
+                Some(port_info) => port_info.owner = new_cid,
+                None => unreachable!(),
+            }
         }
-        cu.inner.native_ports.retain(|port| !ports.contains(port));
-        // 4. add new component
-        cu.proto_components.insert(
-            new_cid,
-            ProtoComponent {
-                state: cu.proto_description.new_main_component(identifier, ports),
-                ports: ports.iter().copied().collect(),
-            },
-        );
         Ok(())
     }
 }