diff --git a/p2p/simulations/adapters/inproc.go b/p2p/simulations/adapters/inproc.go
index d80f7051d9..b75538ee9f 100644
--- a/p2p/simulations/adapters/inproc.go
+++ b/p2p/simulations/adapters/inproc.go
@@ -35,9 +35,8 @@ import (
 // SimAdapter is a NodeAdapter which creates in-memory nodes and connects them
 // using an in-memory p2p.MsgReadWriter pipe
 type SimAdapter struct {
-	mtx      sync.RWMutex
-	nodes    map[discover.NodeID]*SimNode
-	services map[string]ServiceFunc
+	mtx   sync.RWMutex
+	nodes map[discover.NodeID]*SimNode
 }
 
 // NewSimAdapter creates a SimAdapter which is capable of running in-memory
@@ -45,8 +44,7 @@ type SimAdapter struct {
 // node is passed to the NewNode function in the NodeConfig)
 func NewSimAdapter(services map[string]ServiceFunc) *SimAdapter {
 	return &SimAdapter{
-		nodes:    make(map[discover.NodeID]*SimNode),
-		services: services,
+		nodes: make(map[discover.NodeID]*SimNode),
 	}
 }
 
@@ -88,12 +86,6 @@ func (s *SimAdapter) NewNode(config *NodeConfig) (Node, error) {
 	//}
 	//service := serviceFunc(id)
 
-	for _, service := range s.services[config.Service](id, nil) {
-		for _, proto := range service.Protocols() {
-			nodeprotos = append(nodeprotos, proto)
-		}
-	}
-
 	_, err := node.New(&node.Config{
 		P2P: p2p.Config{
 			PrivateKey:      config.PrivateKey,
@@ -103,15 +95,20 @@ func (s *SimAdapter) NewNode(config *NodeConfig) (Node, error) {
 			Dialer:          s,
 			EnableMsgEvents: true,
 		},
-		NoUSB: true,
 	})
 	if err != nil {
 		return nil, err
 	}
 
+	for _, service := range serviceFuncs[config.Service](id, nil) {
+		for _, proto := range service.Protocols() {
+			nodeprotos = append(nodeprotos, proto)
+		}
+	}
+
 	simnode := &SimNode{
 		Id:          id,
-		serviceFunc: s.services[config.Service],
+		serviceFunc: serviceFuncs[config.Service],
 		adapter:     s,
 		config:      config,
 		running:     []node.Service{},
@@ -284,7 +281,7 @@ func (self *SimNode) Stop() error {
 	return nil
 }
 
-// Service returns the underlying running node.Service matching the supplied servuce type
+// Service returns the underlying running node.Service matching the supplied service type
 func (self *SimNode) Service(servicetype interface{}) node.Service {
 	self.lock.Lock()
 	defer self.lock.Unlock()
diff --git a/p2p/simulations/adapters/types.go b/p2p/simulations/adapters/types.go
index 9d2249651b..4c89a05f0b 100644
--- a/p2p/simulations/adapters/types.go
+++ b/p2p/simulations/adapters/types.go
@@ -20,6 +20,7 @@ import (
 	"crypto/ecdsa"
 	"encoding/hex"
 	"encoding/json"
+	"fmt"
 	"net"
 	"os"
 
@@ -215,11 +216,9 @@ var serviceFuncs = make(Services)
 // start devp2p nodes
 func RegisterServices(services Services) {
 	for name, f := range services {
-		// TODO: FIXME: protocol tester if called more than once, throws an error so for now
-		// just overwrite
-		// if _, exists := serviceFuncs[name]; exists {
-		// 	panic(fmt.Sprintf("node service already exists: %q", name))
-		// }
+		if _, exists := serviceFuncs[name]; exists {
+			panic(fmt.Sprintf("node service already exists: %q", name))
+		}
 		serviceFuncs[name] = f
 	}
 
diff --git a/p2p/testing/protocoltester.go b/p2p/testing/protocoltester.go
index a328cb06d7..069d5bc6f1 100644
--- a/p2p/testing/protocoltester.go
+++ b/p2p/testing/protocoltester.go
@@ -19,8 +19,8 @@ type ProtocolTester struct {
 }
 
 func NewProtocolTester(t *testing.T, id *adapters.NodeId, n int, run func(*p2p.Peer, p2p.MsgReadWriter) error) *ProtocolTester {
-//func NewProtocolTester(t *testing.T, id *adapters.NodeId, n int, run func(*p2p.Peer, p2p.MsgReadWriter) error) *ProtocolTester {
-	services := adapters.Services {
+	//func NewProtocolTester(t *testing.T, id *adapters.NodeId, n int, run func(*p2p.Peer, p2p.MsgReadWriter) error) *ProtocolTester {
+	services := adapters.Services{
 		"test": func(id *adapters.NodeId, _ []byte) []node.Service {
 			return []node.Service{&testNode{run}}
 		},
@@ -28,7 +28,6 @@ func NewProtocolTester(t *testing.T, id *adapters.NodeId, n int, run func(*p2p.P
 			return []node.Service{newMockNode()}
 		},
 	}
-	adapters.RegisterServices(services)
 	adapter := adapters.NewSimAdapter(services)
 	net := simulations.NewNetwork(adapter, &simulations.NetworkConfig{})
 	if _, err := net.NewNodeWithConfig(&adapters.NodeConfig{Id: id, Service: "test"}); err != nil {