diff --git a/docs/config.md b/docs/config.md
index 205872d9..70382e1f 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -280,6 +280,20 @@ Attribute | Description | Default
 `max-outstanding` | Max outstanding sessions | 800
 `start-rate` | Setup request rate in sessions per second | 400
 `stop-rate` | Teardown request rate in sessions per second | 400
+`iterate-vlan-outer` | Iterate on outer VLAN first | false
+
+Per default sessions are created by iteration over inner VLAN range first and outer VLAN second. 
+Which can be changed by `iterate-vlan-outer` to iterate on outer VLAN first and inner VLAN second.
+
+Therefore the following configuration generates the sessions on VLAN (outer:inner) 1:3, 1:4, 2:3, 2:4 per default or alternative 1:3, 2:3, 1:4, 2:4 with `iterate-vlan-outer` enabled. 
+```json
+{
+    "outer-vlan-min": 1,
+    "outer-vlan-max": 2,
+    "inner-vlan-min": 3,
+    "inner-vlan-max": 4
+}
+``` 
 
 ## IPoE
 
diff --git a/src/bbl.c b/src/bbl.c
index ef6a525c..57081655 100644
--- a/src/bbl.c
+++ b/src/bbl.c
@@ -756,8 +756,8 @@ bbl_init_sessions (bbl_ctx_s *ctx)
     access_config = ctx->config.access_config;
 
     /* For equal distribution of sessions over access configurations 
-     * and outer VLAN's, we loop first over all configurations,
-     * second over all outer VLAN's and last over all inner VLAN's. */
+     * and outer VLAN's, we loop first over all configurations and
+     * second over VLAN ranges as per configration. */
     while(i <= ctx->config.sessions) {
         if(access_config->exhausted) goto Next;
         if(access_config->access_outer_vlan == 0) {
@@ -765,15 +765,28 @@ bbl_init_sessions (bbl_ctx_s *ctx)
             access_config->access_outer_vlan = access_config->access_outer_vlan_min;
             access_config->access_inner_vlan = access_config->access_inner_vlan_min;
         } else {
-            access_config->access_outer_vlan++;
-            if(access_config->access_outer_vlan > access_config->access_outer_vlan_max) {
-                access_config->access_outer_vlan = access_config->access_outer_vlan_min;
-                if(access_config->access_inner_vlan <= access_config->access_inner_vlan_max) {
+            if(ctx->config.iterate_outer_vlan) {
+                /* Iterate over outer VLAN first and inner VLAN second */
+                access_config->access_outer_vlan++;
+                if(access_config->access_outer_vlan > access_config->access_outer_vlan_max) {
+                    access_config->access_outer_vlan = access_config->access_outer_vlan_min;
                     access_config->access_inner_vlan++;
                 }
+            } else {
+                /* Iterate over inner VLAN first and outer VLAN second (default) */
+                access_config->access_inner_vlan++;
+                if(access_config->access_inner_vlan > access_config->access_inner_vlan_max) {
+                    access_config->access_inner_vlan = access_config->access_inner_vlan_min;
+                    access_config->access_outer_vlan++;
+                }
             }
         }
-        if(access_config->access_inner_vlan > access_config->access_inner_vlan_max) {
+        if(access_config->access_outer_vlan == 0) {
+            /* This is required to handle untagged interafaces */
+            access_config->exhausted = true;
+        }
+        if(access_config->access_outer_vlan > access_config->access_outer_vlan_max || 
+           access_config->access_inner_vlan > access_config->access_inner_vlan_max) {
             /* VLAN range exhausted */
             access_config->exhausted = true;
             goto Next;
diff --git a/src/bbl.h b/src/bbl.h
index 51b35d26..c7ffd575 100644
--- a/src/bbl.h
+++ b/src/bbl.h
@@ -408,6 +408,7 @@ typedef struct bbl_ctx_
         uint32_t sessions_max_outstanding;
         uint16_t sessions_start_rate;
         uint16_t sessions_stop_rate;
+        bool iterate_outer_vlan;
 
         /* Static */
         uint32_t static_ip;
diff --git a/src/bbl_config.c b/src/bbl_config.c
index 289fbe85..18ca8352 100644
--- a/src/bbl_config.c
+++ b/src/bbl_config.c
@@ -250,6 +250,10 @@ json_parse_config (json_t *root, bbl_ctx_s *ctx) {
         if (json_is_number(value)) {
             ctx->config.sessions_stop_rate = json_number_value(value);
         }
+        value = json_object_get(section, "iterate-vlan-outer");
+        if (json_is_boolean(value)) {
+            ctx->config.iterate_outer_vlan = json_boolean_value(value);
+        }
     }
 
     /* IPoE Configuration */