diff --git a/mem/idealmemcontroller/mock_sim_test.go b/mem/idealmemcontroller/mock_sim_test.go
index b89ee48a..c34db6b8 100644
--- a/mem/idealmemcontroller/mock_sim_test.go
+++ b/mem/idealmemcontroller/mock_sim_test.go
@@ -272,6 +272,20 @@ func (mr *MockConnectionMockRecorder) Hooks() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Hooks", reflect.TypeOf((*MockConnection)(nil).Hooks))
 }
 
+// Name mocks base method.
+func (m *MockConnection) Name() string {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Name")
+	ret0, _ := ret[0].(string)
+	return ret0
+}
+
+// Name indicates an expected call of Name.
+func (mr *MockConnectionMockRecorder) Name() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Name", reflect.TypeOf((*MockConnection)(nil).Name))
+}
+
 // NotifyAvailable mocks base method.
 func (m *MockConnection) NotifyAvailable(arg0 sim.Port) {
 	m.ctrl.T.Helper()
diff --git a/sim/connection.go b/sim/connection.go
index 59f6f6d8..2052b28c 100644
--- a/sim/connection.go
+++ b/sim/connection.go
@@ -11,6 +11,7 @@ func NewSendError() *SendError {
 
 // A Connection is responsible for delivering messages to its destination.
 type Connection interface {
+	Named
 	Hookable
 
 	// PlugIn connects a port to the connection. The connection should reserve
diff --git a/sim/directconnection/builder.go b/sim/directconnection/builder.go
index a23fba7f..077478f5 100644
--- a/sim/directconnection/builder.go
+++ b/sim/directconnection/builder.go
@@ -25,7 +25,11 @@ func (b Builder) WithFreq(f sim.Freq) Builder {
 func (b Builder) Build(name string) *Comp {
 	c := &Comp{}
 	c.TickingComponent = sim.NewSecondaryTickingComponent(name, b.engine, b.freq, c)
-	middleware := &middleware{Comp: c}
+
+	middleware := &middleware{
+		Comp: c,
+	}
 	c.AddMiddleware(middleware)
+
 	return c
 }
diff --git a/sim/directconnection/directconnection.go b/sim/directconnection/directconnection.go
index d542e160..8f7ccbbe 100644
--- a/sim/directconnection/directconnection.go
+++ b/sim/directconnection/directconnection.go
@@ -80,7 +80,9 @@ func (m *middleware) forwardMany(
 			break
 		}
 
-		err := head.Meta().Dst.Deliver(head)
+		dst := head.Meta().Dst
+
+		err := dst.Deliver(head)
 		if err != nil {
 			break
 		}
diff --git a/sim/directconnection/mock_sim_test.go b/sim/directconnection/mock_sim_test.go
index d422fb26..972bfb25 100644
--- a/sim/directconnection/mock_sim_test.go
+++ b/sim/directconnection/mock_sim_test.go
@@ -464,6 +464,20 @@ func (mr *MockConnectionMockRecorder) Hooks() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Hooks", reflect.TypeOf((*MockConnection)(nil).Hooks))
 }
 
+// Name mocks base method.
+func (m *MockConnection) Name() string {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Name")
+	ret0, _ := ret[0].(string)
+	return ret0
+}
+
+// Name indicates an expected call of Name.
+func (mr *MockConnectionMockRecorder) Name() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Name", reflect.TypeOf((*MockConnection)(nil).Name))
+}
+
 // NotifyAvailable mocks base method.
 func (m *MockConnection) NotifyAvailable(arg0 sim.Port) {
 	m.ctrl.T.Helper()
diff --git a/sim/mock_sim_test.go b/sim/mock_sim_test.go
index af4c4499..6c84be11 100644
--- a/sim/mock_sim_test.go
+++ b/sim/mock_sim_test.go
@@ -463,6 +463,20 @@ func (mr *MockConnectionMockRecorder) Hooks() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Hooks", reflect.TypeOf((*MockConnection)(nil).Hooks))
 }
 
+// Name mocks base method.
+func (m *MockConnection) Name() string {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Name")
+	ret0, _ := ret[0].(string)
+	return ret0
+}
+
+// Name indicates an expected call of Name.
+func (mr *MockConnectionMockRecorder) Name() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Name", reflect.TypeOf((*MockConnection)(nil).Name))
+}
+
 // NotifyAvailable mocks base method.
 func (m *MockConnection) NotifyAvailable(arg0 Port) {
 	m.ctrl.T.Helper()
diff --git a/sim/port.go b/sim/port.go
index dfbee3be..83eb45bf 100644
--- a/sim/port.go
+++ b/sim/port.go
@@ -1,6 +1,7 @@
 package sim
 
 import (
+	"fmt"
 	"sync"
 )
 
@@ -51,6 +52,16 @@ var HookPosPortMsgRetrieve = &HookPos{Name: "Port Msg Retrieve"}
 
 // SetConnection sets which connection plugged in to this port.
 func (p *LimitNumMsgPort) SetConnection(conn Connection) {
+	if p.conn != nil {
+		connName := p.conn.Name()
+		newConnName := conn.Name()
+		panicMsg := fmt.Sprintf(
+			"connection already set to %s, now connecting to %s",
+			connName, newConnName,
+		)
+		panic(panicMsg)
+	}
+
 	p.conn = conn
 }