diff --git a/src/runtime2/communication.rs b/src/runtime2/communication.rs
index 7f84183fdc9885c463fad673a24142500abeceb7..f879550f7307f7dc5a0b96d908adab1299f2175e 100644
--- a/src/runtime2/communication.rs
+++ b/src/runtime2/communication.rs
@@ -79,30 +79,37 @@ pub struct SyncMessage {
 }
 
 #[derive(Debug)]
-pub struct SyncLocalSolutionEntry {
-    pub self_port_id: PortId,
-    pub peer_comp_id: CompId,
-    pub peer_port_id: PortId,
-    pub mapping: u32,
-    pub port_kind: PortKind,
+pub enum SyncLocalSolutionEntry {
+    Putter(SyncSolutionPutterPort),
+    Getter(SyncSolutionGetterPort),
 }
 
 pub type SyncLocalSolution = Vec<SyncLocalSolutionEntry>;
 
+/// Getter port in a solution. Upon receiving a message it is certain about who
+/// its peer is.
 #[derive(Debug)]
-pub struct SyncSolutionPort {
+pub struct SyncSolutionGetterPort {
     pub self_comp_id: CompId,
     pub self_port_id: PortId,
     pub peer_comp_id: CompId,
     pub peer_port_id: PortId,
     pub mapping: u32,
-    pub port_kind: PortKind,
+}
+
+/// Putter port in a solution. A putter may not be certain about who its peer
+/// component/port is.
+#[derive(Debug)]
+pub struct SyncSolutionPutterPort {
+    pub self_comp_id: CompId,
+    pub self_port_id: PortId,
+    pub mapping: u32,
 }
 
 #[derive(Debug)]
 pub struct SyncSolutionChannel {
-    pub putter: Option<SyncSolutionPort>,
-    pub getter: Option<SyncSolutionPort>,
+    pub putter: Option<SyncSolutionPutterPort>,
+    pub getter: Option<SyncSolutionGetterPort>,
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
@@ -114,16 +121,16 @@ pub enum SyncRoundDecision {
 
 #[derive(Debug)]
 pub struct SyncPartialSolution {
-    pub submissions_by: Vec<(CompId, bool)>,
     pub channel_mapping: Vec<SyncSolutionChannel>,
+    pub matched_channels: usize,
     pub decision: SyncRoundDecision,
 }
 
 impl Default for SyncPartialSolution {
     fn default() -> Self {
         return Self{
-            submissions_by: Vec::new(),
             channel_mapping: Vec::new(),
+            matched_channels: 0,
             decision: SyncRoundDecision::None,
         }
     }