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diff --git a/vnet/vnet/l2/feat_bitmap.h b/vnet/vnet/l2/feat_bitmap.h
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+++ b/vnet/vnet/l2/feat_bitmap.h
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+/*
+ * feat_bitmap.h: bitmap for managing feature invocation
+ *
+ * Copyright (c) 2013 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef included_vnet_l2_feat_bitmap_h
+#define included_vnet_l2_feat_bitmap_h
+
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+
+/* 
+ * The feature bitmap is a way of organizing input and output feature graph nodes.
+ * The set of features to be executed are arranged in a bitmap with one bit per 
+ * feature and each bit positioned in the same order that the features should be 
+ * executed. Features can be dynamically removed from the set by masking off their 
+ * corresponding bits. The bitmap is stored in packet context. Each feature clears
+ * its bit and then calls feat_bitmap_get_next_node_index() to go to the next 
+ * graph node.
+ */
+
+
+// 32 features in a u32 bitmap
+#define FEAT_MAX 32
+
+// Initialize the feature next-node indexes of a graph node.
+// Should be called by the init function of each feature graph node.
+always_inline
+void feat_bitmap_init_next_nodes (
+        vlib_main_t  * vm,
+        u32            node_index,   // the current graph node index
+        u32            num_features, // number of entries in feat_names
+        char        ** feat_names,   // array of feature graph node names
+        u32          * next_nodes)   // array of 32 next indexes to init
+{
+  u32 idx;
+
+  ASSERT(num_features <= FEAT_MAX);
+
+  for (idx=0; idx<num_features; idx++) {
+    if (vlib_get_node_by_name(vm, (u8 *) feat_names[idx])) {
+      next_nodes[idx] = 
+          vlib_node_add_named_next(vm, node_index, feat_names[idx]);
+    } else { // Node may be in plugin which is not installed, use drop node
+      next_nodes[idx] = 
+          vlib_node_add_named_next(vm, node_index, "feature-bitmap-drop");
+    }
+  }
+ 
+  // All unassigned bits go to the drop node
+  for (; idx<FEAT_MAX; idx++) {
+    next_nodes[idx] = vlib_node_add_named_next(vm, node_index, "feature-bitmap-drop");
+  }
+}
+
+// Return the graph node index for the feature corresponding to the 
+// first set bit in the bitmap.
+always_inline
+u32 feat_bitmap_get_next_node_index (u32 * next_nodes, u32 bitmap)
+{
+  u32 first_bit;
+
+  count_leading_zeros(first_bit, bitmap);
+  first_bit = uword_bits - 1 - first_bit;
+  return next_nodes[first_bit];
+}
+
+#endif // included_vnet_l2_feat_bitmap_h