diff --git a/src/python/loxi/of11/action.py b/src/python/loxi/of11/action.py
index 53056ea..42f8340 100644
--- a/src/python/loxi/of11/action.py
+++ b/src/python/loxi/of11/action.py
@@ -183,6 +183,61 @@
 
 experimenter.subtypes[6035143] = bsn
 
+class bsn_checksum(bsn):
+    type = 65535
+    experimenter = 6035143
+    subtype = 4
+
+    def __init__(self, checksum=None):
+        if checksum != None:
+            self.checksum = checksum
+        else:
+            self.checksum = 0
+        return
+
+    def pack(self):
+        packed = []
+        packed.append(struct.pack("!H", self.type))
+        packed.append(struct.pack("!H", 0)) # placeholder for len at index 1
+        packed.append(struct.pack("!L", self.experimenter))
+        packed.append(struct.pack("!L", self.subtype))
+        packed.append(util.pack_checksum_128(self.checksum))
+        length = sum([len(x) for x in packed])
+        packed[1] = struct.pack("!H", length)
+        return ''.join(packed)
+
+    @staticmethod
+    def unpack(reader):
+        obj = bsn_checksum()
+        _type = reader.read("!H")[0]
+        assert(_type == 65535)
+        _len = reader.read("!H")[0]
+        orig_reader = reader
+        reader = orig_reader.slice(_len - (2 + 2))
+        _experimenter = reader.read("!L")[0]
+        assert(_experimenter == 6035143)
+        _subtype = reader.read("!L")[0]
+        assert(_subtype == 4)
+        obj.checksum = util.unpack_checksum_128(reader)
+        return obj
+
+    def __eq__(self, other):
+        if type(self) != type(other): return False
+        if self.checksum != other.checksum: return False
+        return True
+
+    def pretty_print(self, q):
+        q.text("bsn_checksum {")
+        with q.group():
+            with q.indent(2):
+                q.breakable()
+                q.text("checksum = ");
+                q.pp(self.checksum)
+            q.breakable()
+        q.text('}')
+
+bsn.subtypes[4] = bsn_checksum
+
 class bsn_mirror(bsn):
     type = 65535
     experimenter = 6035143
diff --git a/src/python/loxi/of11/common.py b/src/python/loxi/of11/common.py
index 88e1c79..99f1d36 100644
--- a/src/python/loxi/of11/common.py
+++ b/src/python/loxi/of11/common.py
@@ -133,7 +133,7 @@
 class bsn_vport_l2gre(bsn_vport):
     type = 1
 
-    def __init__(self, flags=None, port_no=None, local_mac=None, nh_mac=None, src_ip=None, dst_ip=None, dscp=None, ttl=None, vpn=None, if_name=None):
+    def __init__(self, flags=None, port_no=None, loopback_port_no=None, local_mac=None, nh_mac=None, src_ip=None, dst_ip=None, dscp=None, ttl=None, vpn=None, if_name=None):
         if flags != None:
             self.flags = flags
         else:
@@ -142,6 +142,10 @@
             self.port_no = port_no
         else:
             self.port_no = 0
+        if loopback_port_no != None:
+            self.loopback_port_no = loopback_port_no
+        else:
+            self.loopback_port_no = 0
         if local_mac != None:
             self.local_mac = local_mac
         else:
@@ -182,6 +186,7 @@
         packed.append(struct.pack("!H", 0)) # placeholder for length at index 1
         packed.append(struct.pack("!L", self.flags))
         packed.append(util.pack_port_no(self.port_no))
+        packed.append(util.pack_port_no(self.loopback_port_no))
         packed.append(struct.pack("!6B", *self.local_mac))
         packed.append(struct.pack("!6B", *self.nh_mac))
         packed.append(struct.pack("!L", self.src_ip))
@@ -205,6 +210,7 @@
         reader = orig_reader.slice(_length - (2 + 2))
         obj.flags = reader.read("!L")[0]
         obj.port_no = util.unpack_port_no(reader)
+        obj.loopback_port_no = util.unpack_port_no(reader)
         obj.local_mac = list(reader.read('!6B'))
         obj.nh_mac = list(reader.read('!6B'))
         obj.src_ip = reader.read("!L")[0]
@@ -220,6 +226,7 @@
         if type(self) != type(other): return False
         if self.flags != other.flags: return False
         if self.port_no != other.port_no: return False
+        if self.loopback_port_no != other.loopback_port_no: return False
         if self.local_mac != other.local_mac: return False
         if self.nh_mac != other.nh_mac: return False
         if self.src_ip != other.src_ip: return False
@@ -241,6 +248,9 @@
                 q.text("port_no = ");
                 q.text(util.pretty_port(self.port_no))
                 q.text(","); q.breakable()
+                q.text("loopback_port_no = ");
+                q.text(util.pretty_port(self.loopback_port_no))
+                q.text(","); q.breakable()
                 q.text("local_mac = ");
                 q.text(util.pretty_mac(self.local_mac))
                 q.text(","); q.breakable()
diff --git a/src/python/loxi/of11/const.py b/src/python/loxi/of11/const.py
index 3366ba1..a951bcf 100644
--- a/src/python/loxi/of11/const.py
+++ b/src/python/loxi/of11/const.py
@@ -190,11 +190,13 @@
 OF_BSN_VPORT_L2GRE_LOCAL_MAC_IS_VALID = 1
 OF_BSN_VPORT_L2GRE_DSCP_ASSIGN = 2
 OF_BSN_VPORT_L2GRE_DSCP_COPY = 4
+OF_BSN_VPORT_L2GRE_LOOPBACK_IS_VALID = 8
 
 ofp_bsn_vport_l2gre_flags_map = {
     1: 'OF_BSN_VPORT_L2GRE_LOCAL_MAC_IS_VALID',
     2: 'OF_BSN_VPORT_L2GRE_DSCP_ASSIGN',
     4: 'OF_BSN_VPORT_L2GRE_DSCP_COPY',
+    8: 'OF_BSN_VPORT_L2GRE_LOOPBACK_IS_VALID',
 }
 
 # Identifiers from group ofp_bsn_vport_q_in_q_untagged