diff --git a/private/drkey/drkeyutil/drkey.go b/private/drkey/drkeyutil/drkey.go
index d2a6f6588d..7f34d5e0d7 100644
--- a/private/drkey/drkeyutil/drkey.go
+++ b/private/drkey/drkeyutil/drkey.go
@@ -19,7 +19,7 @@ const (
 	//
 	// Picking the value equal or shorter than half of the drkey Grace Period ensures
 	// that we accept packets for active keys only.
-	DefaultAcceptanceWindowOffset = 2*time.Second + 500*time.Millisecond
+	DefaultAcceptanceWindowLength = 5
 	EnvVarAccpetanceWindow        = "SCION_TESTING_ACCEPTANCE_WINDOW"
 )
 
@@ -38,11 +38,11 @@ func LoadEpochDuration() time.Duration {
 func LoadAcceptanceWindow() time.Duration {
 	s := os.Getenv(EnvVarAccpetanceWindow)
 	if s == "" {
-		return DefaultAcceptanceWindowOffset
+		return DefaultAcceptanceWindowLength
 	}
 	duration, err := util.ParseDuration(s)
 	if err != nil {
-		return DefaultAcceptanceWindowOffset
+		return DefaultAcceptanceWindowLength
 	}
 	return duration
 }
diff --git a/private/drkey/drkeyutil/provider.go b/private/drkey/drkeyutil/provider.go
index a1b9cf335c..4c962d1a32 100644
--- a/private/drkey/drkeyutil/provider.go
+++ b/private/drkey/drkeyutil/provider.go
@@ -56,8 +56,8 @@ func (p *FakeProvider) GetKeyWithinAcceptanceWindow(
 		return drkey.ASHostKey{}, err
 	}
 
-	awBegin := t.Add(-(p.AcceptanceWindow))
-	awEnd := t.Add(p.AcceptanceWindow)
+	awBegin := t.Add(-(p.AcceptanceWindow / 2))
+	awEnd := t.Add(p.AcceptanceWindow / 2)
 	validity := cppki.Validity{
 		NotBefore: awBegin,
 		NotAfter:  awEnd,