diff --git a/openflow15/action.go b/openflow15/action.go
index 559457e..a3bfe3c 100644
--- a/openflow15/action.go
+++ b/openflow15/action.go
@@ -88,7 +88,7 @@ func DecodeAction(data []byte) (Action, error) {
 	case ActionType_PushVlan:
 		a = new(ActionPush)
 	case ActionType_PopVlan:
-		a = new(ActionHeader)
+		a = new(ActionPopVlan)
 	case ActionType_PushMpls:
 		a = new(ActionPush)
 	case ActionType_PopMpls:
diff --git a/openflow15/instruction.go b/openflow15/instruction.go
index 69fe787..688f0a5 100644
--- a/openflow15/instruction.go
+++ b/openflow15/instruction.go
@@ -80,6 +80,10 @@ func DecodeInstr(data []byte) (Instruction, error) {
 		return nil, fmt.Errorf("unknown Instrheader type: %v", t)
 	}
 
+	if a == nil {
+		return nil, fmt.Errorf("No supported Instrheader type: %v", t)
+	}
+
 	err := a.UnmarshalBinary(data)
 	if err != nil {
 		klog.ErrorS(err, "Failed to unmarshal Instruction", "data", data)
diff --git a/openflow15/match.go b/openflow15/match.go
index bb06fa9..9b79135 100644
--- a/openflow15/match.go
+++ b/openflow15/match.go
@@ -566,6 +566,11 @@ func DecodeMatchField(class uint16, field uint8, length uint8, hasMask bool, dat
 			return nil, err
 		}
 
+		if val == nil {
+			err := fmt.Errorf("Not supported field for nxm_1: %v", field)
+			return nil, err
+		}
+
 		err := val.UnmarshalBinary(data)
 		if err != nil {
 			klog.ErrorS(err, "Failed to unmarshal Nxm Field", "data", data)
diff --git a/openflow15/multipart.go b/openflow15/multipart.go
index ac10a7f..859f8ce 100644
--- a/openflow15/multipart.go
+++ b/openflow15/multipart.go
@@ -83,7 +83,7 @@ func (s *MultipartRequest) UnmarshalBinary(data []byte) error {
 			// The request body is empty.
 		case MultipartType_Port:
 			// The request body is struct ofp_port_multipart_request.
-			req = new(PortMultipartRequst)
+			req = new(PortMultipartRequest)
 		case MultipartType_QueueStats:
 			// The request body is struct ofp_queue_multipart_request.
 			req = new(QueueMultipartRequest)
@@ -189,7 +189,6 @@ func (s *MultipartReply) UnmarshalBinary(data []byte) error {
 		return err
 	}
 	n := s.Header.Len()
-
 	s.Type = binary.BigEndian.Uint16(data[n:])
 	n += 2
 	s.Flags = binary.BigEndian.Uint16(data[n:])
@@ -863,29 +862,29 @@ const (
 )
 
 // ofp_port_multipart_request
-type PortMultipartRequst struct {
+type PortMultipartRequest struct {
 	PortNo uint32
 	pad    []uint8 // Size 4
 }
 
-func NewPortStatsRequest(port uint32) *PortMultipartRequst {
-	p := new(PortMultipartRequst)
+func NewPortStatsRequest(port uint32) *PortMultipartRequest {
+	p := new(PortMultipartRequest)
 	p.pad = make([]byte, 4)
 	p.PortNo = port
 	return p
 }
 
-func (s *PortMultipartRequst) Len() (n uint16) {
+func (s *PortMultipartRequest) Len() (n uint16) {
 	return 8
 }
 
-func (s *PortMultipartRequst) MarshalBinary() (data []byte, err error) {
+func (s *PortMultipartRequest) MarshalBinary() (data []byte, err error) {
 	data = make([]byte, int(s.Len()))
 	binary.BigEndian.PutUint32(data, s.PortNo)
 	return
 }
 
-func (s *PortMultipartRequst) UnmarshalBinary(data []byte) error {
+func (s *PortMultipartRequest) UnmarshalBinary(data []byte) error {
 	s.PortNo = binary.BigEndian.Uint32(data)
 	return nil
 }
@@ -2867,33 +2866,12 @@ func (m *MeterFeatures) UnmarshalBinary(data []byte) (err error) {
 	return
 }
 
-// ofp_port_multipart_request
-type PortMultipartRequest struct {
-	PortNo uint32
-	Pad    []byte // 4 bytes
-}
-
 func NewPortMultipartRequest(num uint32) *PortMultipartRequest {
 	n := new(PortMultipartRequest)
 	n.PortNo = num
 	return n
 }
 
-func (p *PortMultipartRequest) Len() uint16 {
-	return 8
-}
-
-func (p *PortMultipartRequest) MarshalBinary() (data []byte, err error) {
-	data = make([]byte, p.Len())
-	binary.BigEndian.PutUint32(data[0:], p.PortNo)
-	return
-}
-
-func (p *PortMultipartRequest) UnmarshalBinary(data []byte) (err error) {
-	p.PortNo = binary.BigEndian.Uint32(data)
-	return
-}
-
 // ofp_queue_desc
 type QueueDesc struct {
 	PortNo     uint32
diff --git a/openflow15/openflow15.go b/openflow15/openflow15.go
index fd58f47..11ccd87 100644
--- a/openflow15/openflow15.go
+++ b/openflow15/openflow15.go
@@ -1510,7 +1510,9 @@ func (p *PropExperimenter) Len() uint16 {
 	l := uint16(len(p.Data) * 4)
 	n += l
 	//n += uint16((8 - (l % 8)) % 8)  // pad to make multiple of 8
-	n += uint16(8 - (l % 8)) // pad to make multiple of 8
+	//n += uint16(8 - (l % 8)) // pad to make multiple of 8
+	n += uint16((8 - (n % 8)) % 8) // pad to make multiple of 8
+
 	return n
 }
 
@@ -1547,7 +1549,7 @@ func (p *PropExperimenter) UnmarshalBinary(data []byte) (err error) {
 	p.ExpType = binary.BigEndian.Uint32(data[n:])
 	n += 4
 
-	for n < p.Header.Length+p.Header.Len() {
+	for n < p.Header.Length {
 		d := binary.BigEndian.Uint32(data[n:])
 		p.Data = append(p.Data, d)
 		n += 4