diff --git a/swarm/network/simulation/connect.go b/swarm/network/simulation/connect.go
index 3fe82052b5..f652d3b1c4 100644
--- a/swarm/network/simulation/connect.go
+++ b/swarm/network/simulation/connect.go
@@ -54,7 +54,7 @@ func (s *Simulation) ConnectToLastNode(id discover.NodeID) (err error) {
 // ConnectToRandomNode connects the node with provieded NodeID
 // to a random node that is up.
 func (s *Simulation) ConnectToRandomNode(id discover.NodeID) (err error) {
-	n := s.randomUpNode(id)
+	n := s.RandomUpNode(id)
 	if n == nil {
 		return ErrNodeNotFound
 	}
diff --git a/swarm/network/simulation/node.go b/swarm/network/simulation/node.go
index bc433cfd83..8ea3dd5049 100644
--- a/swarm/network/simulation/node.go
+++ b/swarm/network/simulation/node.go
@@ -294,7 +294,7 @@ func (s *Simulation) StopNode(id discover.NodeID) (err error) {
 
 // StopRandomNode stops a random node.
 func (s *Simulation) StopRandomNode() (id discover.NodeID, err error) {
-	n := s.randomUpNode()
+	n := s.RandomUpNode()
 	if n == nil {
 		return id, ErrNodeNotFound
 	}
@@ -324,18 +324,18 @@ func init() {
 	rand.Seed(time.Now().UnixNano())
 }
 
-// randomUpNode returns a random SimNode that is up.
+// RandomUpNode returns a random SimNode that is up.
 // Arguments are NodeIDs for nodes that should not be returned.
-func (s *Simulation) randomUpNode(exclude ...discover.NodeID) *adapters.SimNode {
+func (s *Simulation) RandomUpNode(exclude ...discover.NodeID) *adapters.SimNode {
 	return s.randomNode(s.UpNodeIDs(), exclude...)
 }
 
-// randomUpNode returns a random SimNode that is not up.
+// randomDownNode returns a random SimNode that is not up.
 func (s *Simulation) randomDownNode(exclude ...discover.NodeID) *adapters.SimNode {
 	return s.randomNode(s.DownNodeIDs(), exclude...)
 }
 
-// randomUpNode returns a random SimNode from the slice of NodeIDs.
+// randomNode returns a random SimNode from the slice of NodeIDs.
 func (s *Simulation) randomNode(ids []discover.NodeID, exclude ...discover.NodeID) *adapters.SimNode {
 	for _, e := range exclude {
 		var i int
diff --git a/swarm/network/simulation/service.go b/swarm/network/simulation/service.go
index d1cbf1f8b3..02e7ad0cc9 100644
--- a/swarm/network/simulation/service.go
+++ b/swarm/network/simulation/service.go
@@ -39,7 +39,7 @@ func (s *Simulation) Service(name string, id discover.NodeID) node.Service {
 // RandomService returns a single Service by name on a
 // randomly chosen node that is up.
 func (s *Simulation) RandomService(name string) node.Service {
-	n := s.randomUpNode()
+	n := s.RandomUpNode()
 	if n == nil {
 		return nil
 	}
diff --git a/swarm/network/stream/common_test.go b/swarm/network/stream/common_test.go
index 2c71ca0ae1..3241511a06 100644
--- a/swarm/network/stream/common_test.go
+++ b/swarm/network/stream/common_test.go
@@ -384,6 +384,10 @@ func uploadFilesToNodes(sim *simulation.Simulation) ([]storage.Address, []string
 	return rootAddrs, rfiles, nil
 }
 
+func init() {
+	rand.Seed(time.Now().UnixNano())
+}
+
 //generate a random file (string)
 func generateRandomFile() (string, error) {
 	//generate a random file size between minFileSize and maxFileSize
diff --git a/swarm/network/stream/snapshot_retrieval_test.go b/swarm/network/stream/snapshot_retrieval_test.go
index 8c857237a1..c95c0f773a 100644
--- a/swarm/network/stream/snapshot_retrieval_test.go
+++ b/swarm/network/stream/snapshot_retrieval_test.go
@@ -18,7 +18,6 @@ package stream
 import (
 	"context"
 	"fmt"
-	"math/rand"
 	"os"
 	"sync"
 	"testing"
@@ -343,17 +342,15 @@ func runRetrievalTest(chunkCount int, nodeCount int) error {
 		//uploadFinished := make(chan struct{})
 		//channel to trigger new node checks
 
-		//select one index at random...
-		idx := rand.Intn(len(nodeIDs))
-		//...and get the the node at that index
+		//get the the node at that index
 		//this is the node selected for upload
-		node := nodeIDs[idx]
-		item, ok := sim.NodeItem(node, bucketKeyStore)
+		node := sim.RandomUpNode()
+		item, ok := sim.NodeItem(node.ID, bucketKeyStore)
 		if !ok {
 			return fmt.Errorf("No localstore")
 		}
 		lstore := item.(*storage.LocalStore)
-		conf.hashes, err = uploadFileToSingleNodeStore(node, chunkCount, lstore)
+		conf.hashes, err = uploadFileToSingleNodeStore(node.ID, chunkCount, lstore)
 		if err != nil {
 			return err
 		}
diff --git a/swarm/network/stream/snapshot_sync_test.go b/swarm/network/stream/snapshot_sync_test.go
index 0428cfe09e..63dd6c305e 100644
--- a/swarm/network/stream/snapshot_sync_test.go
+++ b/swarm/network/stream/snapshot_sync_test.go
@@ -20,7 +20,6 @@ import (
 	crand "crypto/rand"
 	"fmt"
 	"io"
-	"math/rand"
 	"os"
 	"sync"
 	"testing"
@@ -56,10 +55,6 @@ type synctestConfig struct {
 	addrToIdMap      map[string]discover.NodeID
 }
 
-func init() {
-	rand.Seed(time.Now().Unix())
-}
-
 //This test is a syncing test for nodes.
 //One node is randomly selected to be the pivot node.
 //A configurable number of chunks and nodes can be
@@ -191,17 +186,15 @@ func testSyncing(t *testing.T, chunkCount int, nodeCount int) {
 			conf.addrToIdMap[string(a)] = n
 		}
 
-		//select one index at random...
-		idx := rand.Intn(len(nodeIDs))
-		//...and get the the node at that index
+		//get the the node at that index
 		//this is the node selected for upload
-		node := nodeIDs[idx]
-		item, ok := sim.NodeItem(node, bucketKeyStore)
+		node := sim.RandomUpNode()
+		item, ok := sim.NodeItem(node.ID, bucketKeyStore)
 		if !ok {
 			return fmt.Errorf("No localstore")
 		}
 		lstore := item.(*storage.LocalStore)
-		hashes, err := uploadFileToSingleNodeStore(node, chunkCount, lstore)
+		hashes, err := uploadFileToSingleNodeStore(node.ID, chunkCount, lstore)
 		if err != nil {
 			return err
 		}
@@ -403,17 +396,15 @@ func runSyncTest(chunkCount int, nodeCount int) error {
 				}
 			}
 		}()
-		//select one index at random...
-		idx := rand.Intn(len(nodeIDs))
-		//...and get the the node at that index
+		//get the the node at that index
 		//this is the node selected for upload
-		node := nodeIDs[idx]
-		item, ok := sim.NodeItem(node, bucketKeyStore)
+		node := sim.RandomUpNode()
+		item, ok := sim.NodeItem(node.ID, bucketKeyStore)
 		if !ok {
 			return fmt.Errorf("No localstore")
 		}
 		lstore := item.(*storage.LocalStore)
-		hashes, err := uploadFileToSingleNodeStore(node, chunkCount, lstore)
+		hashes, err := uploadFileToSingleNodeStore(node.ID, chunkCount, lstore)
 		if err != nil {
 			return err
 		}