diff --git a/common/stp.cpp b/common/stp.cpp
new file mode 100644
index 0000000..69b7ff3
--- /dev/null
+++ b/common/stp.cpp
@@ -0,0 +1,548 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#include "stp.h"
+#include <QRegExp>
+
+#define uintToMacStr(num)    \
+    QString("%1").arg(num, 6 * 2, BASE_HEX, QChar('0')) \
+    .replace(QRegExp("([0-9a-fA-F]{2}\\B)"), "\\1:").toUpper()
+#define ONE_BIT(pos) ((unsigned int)(1 << (pos)))
+#define BITS(bit) (bit)
+#define BYTES(byte) (byte)
+#define BYTES_TO_BITS(byte) (byte * 8)
+
+#define STP_LLC 0x424203
+
+StpProtocol::StpProtocol(StreamBase *stream, AbstractProtocol *parent)
+    : AbstractProtocol(stream, parent)
+{
+}
+
+StpProtocol::~StpProtocol()
+{
+}
+
+AbstractProtocol* StpProtocol::createInstance(StreamBase *stream,
+                                              AbstractProtocol *parent)
+{
+    return new StpProtocol(stream, parent);
+}
+
+quint32 StpProtocol::protocolNumber() const
+{
+    return OstProto::Protocol::kStpFieldNumber;
+}
+
+void StpProtocol::protoDataCopyInto(OstProto::Protocol &protocol) const
+{
+    protocol.MutableExtension(OstProto::stp)->CopyFrom(data_);
+    protocol.mutable_protocol_id()->set_id(protocolNumber());
+}
+
+void StpProtocol::protoDataCopyFrom(const OstProto::Protocol &protocol)
+{
+    if (protocol.protocol_id().id() == protocolNumber() &&
+        protocol.HasExtension(OstProto::stp))
+        data_.MergeFrom(protocol.GetExtension(OstProto::stp));
+}
+
+QString StpProtocol::name() const
+{
+    return QString("Spanning Tree Protocol");
+}
+
+QString StpProtocol::shortName() const
+{
+    return QString("STP");
+}
+
+AbstractProtocol::ProtocolIdType StpProtocol::protocolIdType() const
+{
+    return ProtocolIdLlc;
+}
+
+quint32 StpProtocol::protocolId(ProtocolIdType type) const
+{
+    switch(type)
+    {
+        case ProtocolIdLlc:
+            return STP_LLC;
+        default:
+            break;
+    }
+
+    return AbstractProtocol::protocolId(type);
+}
+
+int StpProtocol::fieldCount() const
+{
+    return stp_fieldCount;
+}
+
+AbstractProtocol::FieldFlags StpProtocol::fieldFlags(int index) const
+{
+    AbstractProtocol::FieldFlags flags;
+
+    flags = AbstractProtocol::fieldFlags(index);
+
+    switch (index)
+    {
+        case stp_protocol_id:
+        case stp_version_id:
+        case stp_bpdu_type:
+        case stp_flags:
+        case stp_root_id:
+        case stp_root_path_cost:
+        case stp_bridge_id:
+        case stp_port_id:
+        case stp_message_age:
+        case stp_max_age:
+        case stp_hello_time:
+        case stp_forward_delay:
+            break;
+        default:
+            qFatal("%s: unimplemented case %d in switch", __PRETTY_FUNCTION__,
+                   index);
+            break;
+    }
+    return flags;
+}
+
+QVariant StpProtocol::fieldData(int index, FieldAttrib attrib,
+                                int streamIndex) const
+{
+    QString str[] = {"Topology Change", "Topology Change Acknowledgment"};
+
+    switch (index)
+    {
+        case stp_protocol_id:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Protocol Identifier");
+                case FieldValue:
+                    return data_.protocol_id();
+                case FieldTextValue:
+                    return QString("0x%1").arg(data_.protocol_id(),
+                                               4, BASE_HEX, QChar('0'));
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)data_.protocol_id(),
+                                 (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_version_id:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Version Identifier");
+                case FieldValue:
+                    return data_.protocol_version_id();
+                case FieldTextValue:
+                    return QString("%1").arg(
+                                data_.protocol_version_id());
+                case FieldFrameValue:
+                    return QByteArray(1,
+                                      (char)data_.protocol_version_id());
+                case FieldBitSize:
+                    return BYTES_TO_BITS(1);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_bpdu_type:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("BPDU Type");
+                case FieldValue:
+                    return data_.bpdu_type();
+                case FieldTextValue:
+                    return QString("0x%1").arg(data_.bpdu_type(),
+                                               2, BASE_HEX, QChar('0'));
+                case FieldFrameValue:
+                    return QByteArray(1, (char)data_.bpdu_type());
+                case FieldBitSize:
+                    return BYTES_TO_BITS(1);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_flags:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("BPDU Flags");
+                case FieldValue:
+                    return data_.flags();
+                case FieldTextValue:
+                {
+                    QString strTemp = "(";
+                    if((data_.flags() & ONE_BIT(0))) strTemp += str[0] + ", ";
+                    if((data_.flags() & ONE_BIT(7))) strTemp += str[1] + ", ";
+                    strTemp += ")";
+                    strTemp.replace(", )", ")");
+                    return strTemp;
+                }
+                case FieldFrameValue:
+                    return QByteArray(1, (char)data_.flags());
+                case FieldBitSize:
+                    return BYTES_TO_BITS(1);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_root_id:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Root Identifier");
+                case FieldValue:
+                    return (qulonglong) data_.root_id();
+                case FieldTextValue:
+                {
+                    // Root ID contain two value:
+                    // Root ID Priority(first 2 bytes)
+                    // and Root ID MAC (last 6 bytes). (IEEE802.1D-2008)
+                    quint16 priority = (
+                        data_.root_id() & 0xFFFF000000000000) >> (BYTES_TO_BITS(6));
+                    quint64 mac = data_.root_id() & 0x0000FFFFFFFFFFFF;
+                    return QString("Priority: %1 / MAC: %2")
+                            .arg(QString::number(priority), 
+                        uintToMacStr(mac));
+                }
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(8));
+                    qToBigEndian((quint64)data_.root_id(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(8);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_root_path_cost:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Root Path Cost");
+                case FieldValue:
+                    return data_.root_path_cost();
+                case FieldTextValue:
+                    return QString("%1").arg(data_.root_path_cost());
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(4));
+                    qToBigEndian(data_.root_path_cost(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(4);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_bridge_id:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Bridge Identifier");
+                case FieldValue:
+                    return (qulonglong) data_.bridge_id();
+                case FieldTextValue:
+                {
+                    // Bridge ID contain two value:
+                    // Bridge ID Priority(first 2 bytes)
+                    // and Bridge ID MAC (last 6 bytes). (IEEE802.1D-2008)
+                    quint16 priority = (data_.bridge_id() & 0xFFFF000000000000
+                                        ) >> (BYTES_TO_BITS(6));
+                    quint64 mac = data_.bridge_id() & 0x0000FFFFFFFFFFFF;
+                    return QString("Priority: %1 / MAC: %2").arg(QString::number(priority),
+                                                  uintToMacStr(mac));
+                }
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(8));
+                    qToBigEndian((quint64)data_.bridge_id(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(8);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_port_id:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Port Identifier");
+                case FieldValue:
+                    return data_.port_id();
+                case FieldTextValue:
+                    return QString("0x%1").arg(data_.port_id(), 4,
+                                               BASE_HEX, QChar('0'));
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)data_.port_id(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_message_age:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Message Age");
+                case FieldValue:
+                    return data_.message_age();
+                case FieldTextValue:
+                    return QString("%1").arg(data_.message_age());
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)(data_.message_age()),
+                                 (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_max_age:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Max Age");
+                case FieldValue:
+                    return data_.max_age();
+                case FieldTextValue:
+                    return QString("%1").arg(data_.max_age());
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)data_.max_age(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_hello_time:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Hello Time");
+                case FieldValue:
+                    return data_.hello_time();
+                case FieldTextValue:
+                    return QString("%1").arg(data_.hello_time());
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)data_.hello_time(), (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        case stp_forward_delay:
+        {
+            switch (attrib)
+            {
+                case FieldName:
+                    return QString("Forward Delay");
+                case FieldValue:
+                    return data_.forward_delay();
+                case FieldTextValue:
+                    return QString("%1").arg(data_.forward_delay());
+                case FieldFrameValue:
+                {
+                    QByteArray fv;
+                    fv.resize(BYTES(2));
+                    qToBigEndian((quint16)data_.forward_delay(),
+                                 (uchar*)fv.data());
+                    return fv;
+                }
+                case FieldBitSize:
+                    return BYTES_TO_BITS(2);
+                default:
+                    break;
+            }
+            break;
+        }
+        default:
+            break;
+    }
+    return AbstractProtocol::fieldData(index, attrib, streamIndex);
+}
+
+bool StpProtocol::setFieldData(int index, const QVariant &value,
+        FieldAttrib attrib)
+{
+    bool isOk = false;
+
+    if (attrib != FieldValue)
+        return isOk;
+
+    switch (index)
+    {
+        case stp_protocol_id:
+        {
+            quint16 protoId = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_protocol_id(protoId);
+            break;
+        }
+        case stp_version_id:
+        {
+            quint8 versionId = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_protocol_version_id(versionId);
+            break;
+        }
+        case stp_bpdu_type:
+        {
+            quint8 bpdu = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_bpdu_type(bpdu);
+            break;
+        }
+        case stp_flags:
+        {
+            quint8 flags = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_flags(flags);
+            break;
+        }
+        case stp_root_id:
+        {
+            quint64 rootId = value.toULongLong(&isOk);
+            if (isOk)
+                data_.set_root_id(rootId);
+            break;
+        }
+        case stp_root_path_cost:
+        {
+            quint32 pathCost = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_root_path_cost(pathCost);
+            break;
+        }
+        case stp_bridge_id:
+        {
+            quint64 bridgeId = value.toULongLong(&isOk);
+            if (isOk)
+                data_.set_bridge_id(bridgeId);
+            break;
+        }
+        case stp_port_id:
+        {
+            quint32 port_id = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_port_id(port_id);
+            break;
+        }
+        case stp_message_age:
+        {
+            quint32 messageAge = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_message_age(messageAge);
+            break;
+        }
+        case stp_max_age:
+        {
+            quint32 maxAge = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_max_age(maxAge);
+            break;
+        }
+        case stp_hello_time:
+        {
+            quint32 helloTime = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_hello_time(helloTime);
+            break;
+        }
+        case stp_forward_delay:
+        {
+            quint32 forwardDelay = value.toUInt(&isOk);
+            if (isOk)
+                data_.set_forward_delay(forwardDelay);
+            break;
+        }
+        default:
+            break;
+    }
+    return isOk;
+}
diff --git a/common/stp.h b/common/stp.h
new file mode 100644
index 0000000..9148e7c
--- /dev/null
+++ b/common/stp.h
@@ -0,0 +1,111 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#ifndef _STP_H
+#define _STP_H
+
+#include "abstractprotocol.h"
+#include "stp.pb.h"
+
+/*
+Stp Protocol Frame Format -
+    +------------------------------------+------------------+------------------+
+    |              Protocol ID           |   Protocol VID   |     BPDU type    |
+    |                 (16)               |         (8)      |      (8)         |
+    +------------------+-----------------+------------------+------------------+
+    |     Flags        |                    Root Identifier                  ->|
+    |      (8)         |                         (64)                        ->|
+    +------------------+-------------------------------------------------------+
+    |->                              Root Identifier                         ->|
+    |->                                (64)                                  ->|
+    +------------------+-------------------------------------------------------+
+    |-> Root Identifier|                       Root Path Cost                ->|
+    |->    (8)         |                         (32)                        ->|
+    +------------------+-------------------------------------------------------+
+    |-> Root Path Cost |                       Bridge Identifier             ->|
+    |->    (32)        |                         (64)                        ->|
+    +------------------+-------------------------------------------------------+
+    |->                             Bridge Identifier                        ->|
+    |->                                 (64)                                 ->|
+    +------------------+--------------------------------- --+------------------+
+    |-> Bridge Identif.|           Port Identifier          |   Message Age  ->|
+    |->    (64)        |                (16)                |      (16)      ->|
+    +------------------+------------------------------------+------------------+
+    |->  Message Age   |               Max Age              |     Hello Time ->|
+    |->    (16)        |                (16)                |      (16)      ->|
+    +------------------+------------------------------------+------------------+
+    |->  Hello Time    |            Forward delay           |
+    |->    (16)        |                (16)                |
+    +------------------+------------------------------------+
+Figures in brackets represent field width in bits
+*/
+
+class StpProtocol : public AbstractProtocol
+{
+public:
+    enum stpfield
+    {
+        stp_protocol_id = 0,
+        stp_version_id,
+        stp_bpdu_type,
+        stp_flags,
+        stp_root_id,
+        stp_root_path_cost,
+        stp_bridge_id,
+        stp_port_id,
+        stp_message_age,
+        stp_max_age,
+        stp_hello_time,
+        stp_forward_delay,
+
+        stp_fieldCount
+    };
+
+    StpProtocol(StreamBase *stream, AbstractProtocol *parent = 0);
+    virtual ~StpProtocol();
+
+    static AbstractProtocol* createInstance(StreamBase *stream,
+                                            AbstractProtocol *parent = 0);
+    virtual quint32 protocolNumber() const;
+
+    virtual void protoDataCopyInto(OstProto::Protocol &protocol) const;
+    virtual void protoDataCopyFrom(const OstProto::Protocol &protocol);
+
+    virtual ProtocolIdType protocolIdType() const;
+    virtual quint32 protocolId(ProtocolIdType type) const;
+
+    virtual QString name() const;
+    virtual QString shortName() const;
+
+    virtual int fieldCount() const;
+
+    virtual AbstractProtocol::FieldFlags fieldFlags(int index) const;
+    virtual QVariant fieldData(int index, FieldAttrib attrib,
+                               int streamIndex = 0) const;
+    virtual bool setFieldData(int index, const QVariant &value,
+                              FieldAttrib attrib = FieldValue);
+
+
+private:
+    OstProto::Stp    data_;
+};
+
+#endif
diff --git a/common/stp.proto b/common/stp.proto
new file mode 100644
index 0000000..82d0e07
--- /dev/null
+++ b/common/stp.proto
@@ -0,0 +1,44 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+import "protocol.proto";
+
+package OstProto;
+
+// Spanning Tree Protocol
+message Stp {
+    optional uint32    protocol_id = 1 [default = 0x0000];
+    optional uint32    protocol_version_id = 2 [default = 0x00];
+    optional uint32    bpdu_type = 3 [default = 0x00];
+    optional uint32    flags = 4;
+    optional uint64    root_id = 5;
+    optional uint32    root_path_cost = 6;
+    optional uint64    bridge_id = 7;
+    optional uint32    port_id = 8;
+    optional uint32    message_age = 9;
+    optional uint32    max_age = 10;
+    optional uint32    hello_time = 11;
+    optional uint32    forward_delay = 12;
+}
+
+extend Protocol {
+    optional Stp stp = 210;
+}
diff --git a/common/stp.ui b/common/stp.ui
new file mode 100644
index 0000000..741918d
--- /dev/null
+++ b/common/stp.ui
@@ -0,0 +1,510 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Stp</class>
+ <widget class="QWidget" name="Stp">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>615</width>
+    <height>378</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout_4">
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_2">
+     <property name="topMargin">
+      <number>0</number>
+     </property>
+     <item>
+      <layout class="QGridLayout" name="gridLayout_5">
+       <item row="0" column="0" colspan="2">
+        <widget class="QLabel" name="label_22">
+         <property name="text">
+          <string>Protocol Identifier</string>
+         </property>
+         <property name="alignment">
+          <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+         </property>
+        </widget>
+       </item>
+       <item row="0" column="2">
+        <widget class="QLineEdit" name="ui_protocol_id">
+         <property name="enabled">
+          <bool>true</bool>
+         </property>
+         <property name="inputMask">
+          <string/>
+         </property>
+         <property name="text">
+          <string/>
+         </property>
+         <property name="maxLength">
+          <number>5</number>
+         </property>
+         <property name="cursorPosition">
+          <number>0</number>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="0" colspan="2">
+        <widget class="QLabel" name="label_24">
+         <property name="text">
+          <string>Version  Identifier</string>
+         </property>
+         <property name="alignment">
+          <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+         </property>
+         <property name="buddy">
+          <cstring>ui_version_id</cstring>
+         </property>
+        </widget>
+       </item>
+       <item row="1" column="2">
+        <widget class="QLineEdit" name="ui_version_id">
+         <property name="enabled">
+          <bool>true</bool>
+         </property>
+         <property name="inputMask">
+          <string/>
+         </property>
+         <property name="text">
+          <string/>
+         </property>
+         <property name="maxLength">
+          <number>3</number>
+         </property>
+         <property name="cursorPosition">
+          <number>0</number>
+         </property>
+        </widget>
+       </item>
+       <item row="2" column="2">
+        <widget class="QLineEdit" name="ui_bpdu_type">
+         <property name="inputMask">
+          <string/>
+         </property>
+         <property name="text">
+          <string/>
+         </property>
+         <property name="maxLength">
+          <number>3</number>
+         </property>
+        </widget>
+       </item>
+       <item row="2" column="0" colspan="2">
+        <widget class="QLabel" name="label_27">
+         <property name="text">
+          <string>BPDU Type</string>
+         </property>
+         <property name="alignment">
+          <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+         </property>
+        </widget>
+       </item>
+       <item row="3" column="2">
+        <layout class="QHBoxLayout" name="horizontalLayout">
+         <property name="sizeConstraint">
+          <enum>QLayout::SetDefaultConstraint</enum>
+         </property>
+         <item>
+          <widget class="QCheckBox" name="ui_flags_tc_check">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+           <property name="text">
+            <string>TC</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QCheckBox" name="ui_flags_tca_check">
+           <property name="text">
+            <string>TCA</string>
+           </property>
+          </widget>
+         </item>
+        </layout>
+       </item>
+       <item row="3" column="0" colspan="2">
+        <widget class="QLabel" name="label">
+         <property name="layoutDirection">
+          <enum>Qt::LeftToRight</enum>
+         </property>
+         <property name="text">
+          <string>BPDU Flags</string>
+         </property>
+        </widget>
+       </item>
+      </layout>
+     </item>
+     <item>
+      <widget class="QGroupBox" name="groupBox">
+       <property name="title">
+        <string>Root Identifier</string>
+       </property>
+       <layout class="QVBoxLayout" name="verticalLayout">
+        <property name="leftMargin">
+         <number>9</number>
+        </property>
+        <property name="rightMargin">
+         <number>9</number>
+        </property>
+        <item>
+         <layout class="QGridLayout" name="gridLayout_3">
+          <item row="1" column="1">
+           <widget class="QLineEdit" name="ui_root_id">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="inputMask">
+             <string>&gt;HH HH HH HH HH HH; </string>
+            </property>
+            <property name="text">
+             <string>     </string>
+            </property>
+            <property name="cursorPosition">
+             <number>17</number>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_11">
+            <property name="text">
+             <string>Priority</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QLineEdit" name="ui_root_id_priority">
+            <property name="inputMask">
+             <string/>
+            </property>
+            <property name="maxLength">
+             <number>5</number>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_13">
+            <property name="text">
+             <string>MAC Address</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="0">
+           <widget class="QLabel" name="label_3">
+            <property name="text">
+             <string>Path Cost</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="1">
+           <widget class="QLineEdit" name="ui_root_path_cost">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="inputMask">
+             <string/>
+            </property>
+            <property name="text">
+             <string/>
+            </property>
+            <property name="maxLength">
+             <number>10</number>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </item>
+       </layout>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_3">
+     <property name="topMargin">
+      <number>0</number>
+     </property>
+     <property name="bottomMargin">
+      <number>0</number>
+     </property>
+     <item>
+      <widget class="QGroupBox" name="groupBox_2">
+       <property name="title">
+        <string>Bridge Identifier</string>
+       </property>
+       <layout class="QVBoxLayout" name="verticalLayout_2">
+        <property name="leftMargin">
+         <number>0</number>
+        </property>
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <item>
+         <layout class="QGridLayout" name="gridLayout">
+          <item row="1" column="1">
+           <widget class="QLineEdit" name="ui_bridge_id">
+            <property name="inputMask">
+             <string>&gt;HH HH HH HH HH HH; </string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_15">
+            <property name="text">
+             <string>Priority</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_17">
+            <property name="text">
+             <string>MAC Address</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QLineEdit" name="ui_bridge_id_priority">
+            <property name="inputMask">
+             <string/>
+            </property>
+            <property name="maxLength">
+             <number>5</number>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </item>
+       </layout>
+      </widget>
+     </item>
+     <item>
+      <widget class="QGroupBox" name="groupBox_3">
+       <property name="title">
+        <string>Port Identifier</string>
+       </property>
+       <layout class="QVBoxLayout" name="verticalLayout_3">
+        <property name="leftMargin">
+         <number>9</number>
+        </property>
+        <property name="rightMargin">
+         <number>9</number>
+        </property>
+        <item>
+         <layout class="QGridLayout" name="gridLayout_2">
+          <item row="1" column="1">
+           <widget class="QLineEdit" name="ui_port_id_number">
+            <property name="inputMask">
+             <string/>
+            </property>
+            <property name="maxLength">
+             <number>3</number>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_10">
+            <property name="text">
+             <string>Number</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="0">
+           <widget class="QLabel" name="label_2">
+            <property name="text">
+             <string>Priority</string>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QLineEdit" name="ui_port_id_priority">
+            <property name="inputMask">
+             <string/>
+            </property>
+            <property name="text">
+             <string/>
+            </property>
+            <property name="maxLength">
+             <number>3</number>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </item>
+       </layout>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox_4">
+     <property name="title">
+      <string>Timers</string>
+     </property>
+     <property name="alignment">
+      <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+     </property>
+     <property name="flat">
+      <bool>false</bool>
+     </property>
+     <layout class="QHBoxLayout" name="horizontalLayout_4">
+      <property name="leftMargin">
+       <number>0</number>
+      </property>
+      <property name="rightMargin">
+       <number>9</number>
+      </property>
+      <item>
+       <layout class="QGridLayout" name="gridLayout_4">
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <item row="0" column="0">
+         <widget class="QLabel" name="label_6">
+          <property name="text">
+           <string>Message Age (1/256s)</string>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="1">
+         <widget class="QLineEdit" name="ui_message_age">
+          <property name="inputMask">
+           <string/>
+          </property>
+          <property name="text">
+           <string/>
+          </property>
+          <property name="maxLength">
+           <number>5</number>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="0">
+         <widget class="QLabel" name="label_7">
+          <property name="text">
+           <string>Max Age (1/256s)</string>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="1">
+         <widget class="QLineEdit" name="ui_max_age">
+          <property name="inputMask">
+           <string/>
+          </property>
+          <property name="text">
+           <string/>
+          </property>
+          <property name="maxLength">
+           <number>5</number>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+      <item>
+       <layout class="QGridLayout" name="gridLayout_6">
+        <property name="leftMargin">
+         <number>0</number>
+        </property>
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <item row="0" column="0">
+         <widget class="QLabel" name="label_8">
+          <property name="text">
+           <string>Hello Time (1/256s)</string>
+          </property>
+         </widget>
+        </item>
+        <item row="0" column="1">
+         <widget class="QLineEdit" name="ui_hello_time">
+          <property name="inputMask">
+           <string/>
+          </property>
+          <property name="text">
+           <string/>
+          </property>
+          <property name="maxLength">
+           <number>5</number>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="0">
+         <widget class="QLabel" name="label_9">
+          <property name="text">
+           <string>Forward Delay (1/256s)</string>
+          </property>
+         </widget>
+        </item>
+        <item row="1" column="1">
+         <widget class="QLineEdit" name="ui_forward_delay">
+          <property name="inputMask">
+           <string/>
+          </property>
+          <property name="text">
+           <string/>
+          </property>
+          <property name="maxLength">
+           <number>5</number>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+     </layout>
+     <zorder></zorder>
+    </widget>
+   </item>
+   <item>
+    <spacer name="verticalSpacer_3">
+     <property name="orientation">
+      <enum>Qt::Vertical</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>20</width>
+       <height>40</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+  </layout>
+  <zorder>groupBox_4</zorder>
+  <zorder></zorder>
+  <zorder>verticalSpacer_3</zorder>
+ </widget>
+ <tabstops>
+  <tabstop>ui_protocol_id</tabstop>
+  <tabstop>ui_version_id</tabstop>
+  <tabstop>ui_bpdu_type</tabstop>
+  <tabstop>ui_flags_tc_check</tabstop>
+  <tabstop>ui_flags_tca_check</tabstop>
+  <tabstop>ui_root_id_priority</tabstop>
+  <tabstop>ui_root_id</tabstop>
+  <tabstop>ui_root_path_cost</tabstop>
+  <tabstop>ui_bridge_id_priority</tabstop>
+  <tabstop>ui_bridge_id</tabstop>
+  <tabstop>ui_port_id_priority</tabstop>
+  <tabstop>ui_port_id_number</tabstop>
+  <tabstop>ui_message_age</tabstop>
+  <tabstop>ui_max_age</tabstop>
+  <tabstop>ui_hello_time</tabstop>
+  <tabstop>ui_forward_delay</tabstop>
+ </tabstops>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/common/stpconfig.cpp b/common/stpconfig.cpp
new file mode 100644
index 0000000..6144b1a
--- /dev/null
+++ b/common/stpconfig.cpp
@@ -0,0 +1,257 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#include "stpconfig.h"
+#include "stp.h"
+
+#include <QRegExpValidator>
+#include <QIntValidator>
+
+#define ONE_BYTE_MAX 255
+#define TWO_BYTE_MAX 65535
+#define FOUR_BYTE_MAX 4294967295
+#define BIT_0 0
+#define BIT_7 7
+#define ONE_BIT(pos) ((unsigned int)(1 << (pos)))
+#define BYTES(byte) (byte * sizeof(unsigned char))
+#define STR_BYTES_LEN(len) (BYTES(len) * 2)
+
+class UNumberValidator : public QValidator
+{
+private:
+    quint64 min_;
+    quint64 max_;
+    
+public:
+    UNumberValidator(quint64 min, quint64 max, QObject * parent = 0)
+        : QValidator(parent), min_(min), max_(max){}
+    virtual ~UNumberValidator(){}
+
+    virtual QValidator::State validate(QString& input, int& pos) const
+    {
+        QValidator::State state = QValidator::Acceptable;
+        quint64 val = input.toULongLong();
+        if(val < min_ || val > max_)
+            state = QValidator::Invalid;
+        return state;
+    }
+};
+
+
+StpConfigForm::StpConfigForm(QWidget *parent)
+    : AbstractProtocolConfigForm(parent)
+{
+    QRegExp reMac("([0-9,a-f,A-F]{2,2}[:-]){5,5}[0-9,a-f,A-F]{2,2}");
+    setupUi(this);
+
+    QRegExpValidator *validateMACAddress = 
+        new QRegExpValidator(reMac, this);
+    UNumberValidator *validateByte = 
+        new UNumberValidator(0, ONE_BYTE_MAX, this);
+    UNumberValidator *validate2Byte = 
+        new UNumberValidator(0, TWO_BYTE_MAX, this);
+    UNumberValidator *validate4Byte = 
+        new UNumberValidator(0, FOUR_BYTE_MAX, this);
+
+    ui_protocol_id->setValidator(validate2Byte);
+    ui_version_id->setValidator(validateByte);
+
+    ui_bpdu_type->setValidator(validateByte);
+
+    ui_root_id_priority->setValidator(validate2Byte);
+    ui_root_id->setValidator(validateMACAddress);
+
+    ui_root_path_cost->setValidator(validate4Byte);
+
+    ui_bridge_id_priority->setValidator(validate2Byte);
+    ui_bridge_id->setValidator(validateMACAddress);
+
+    ui_port_id_priority->setValidator(validateByte);
+    ui_port_id_number->setValidator(validateByte);
+
+    ui_message_age->setValidator(validate2Byte);
+    ui_max_age->setValidator(validate2Byte);
+    ui_hello_time->setValidator(validate2Byte);
+    ui_forward_delay->setValidator(validate2Byte);
+}
+
+StpConfigForm::~StpConfigForm()
+{
+}
+
+StpConfigForm* StpConfigForm::createInstance()
+{
+    return new StpConfigForm;
+}
+
+void StpConfigForm::loadWidget(AbstractProtocol *proto)
+{
+    bool isOk;
+
+    ui_protocol_id->setText(
+        proto->fieldData(
+            StpProtocol::stp_protocol_id,
+            AbstractProtocol::FieldValue
+        ).toString());
+    ui_version_id->setText(
+        proto->fieldData(
+            StpProtocol::stp_version_id,
+            AbstractProtocol::FieldValue
+        ).toString());
+    ui_bpdu_type->setText(
+        proto->fieldData(
+            StpProtocol::stp_bpdu_type,
+            AbstractProtocol::FieldValue
+        ).toString());
+
+    quint8 flags = proto->fieldData(
+            StpProtocol::stp_flags,
+            AbstractProtocol::FieldValue
+        ).toUInt();
+    ui_flags_tc_check->setChecked(flags & ONE_BIT(BIT_0));
+    ui_flags_tca_check->setChecked(flags & ONE_BIT(BIT_7));
+
+    // root priority value stored as the first two bytes of stp_root_id 
+    // and the last 6 bytes are root MAC address (IEEE802.1D-2008)
+    quint64 rootId = proto->fieldData(
+        StpProtocol::stp_root_id,
+        AbstractProtocol::FieldValue
+        ).toULongLong(&isOk);
+    
+    ui_root_id->setText(
+        QString::number(rootId & 0x0000FFFFFFFFFFFF, BASE_HEX));
+    ui_root_id_priority->setText(QString::number(rootId >> 48));
+    
+    ui_root_path_cost->setText(
+        proto->fieldData(
+            StpProtocol::stp_root_path_cost,
+            AbstractProtocol::FieldValue
+        ).toString());
+
+    // bridge priority value stored as the first two bytes of stp_bridge_id 
+    // and the last 6 bytes are bridge MAC address (IEEE802.1D-2008)
+    quint64 bridgeId = proto->fieldData(
+        StpProtocol::stp_bridge_id,
+        AbstractProtocol::FieldValue
+        ).toULongLong(&isOk);
+
+    ui_bridge_id->setText(
+        QString::number(bridgeId & 0x0000FFFFFFFFFFFF, BASE_HEX));
+    ui_bridge_id_priority->setText(QString::number(bridgeId >> 48));
+
+    // port priority is a first byte of stp_port_id field
+    // and port ID is a second byte (IEEE802.1D-2008)
+    uint portId = proto->fieldData(
+        StpProtocol::stp_port_id,
+        AbstractProtocol::FieldValue
+        ).toUInt(&isOk);
+    
+    ui_port_id_priority->setText(QString::number(portId >> 8));
+    ui_port_id_number->setText(QString::number(portId & ONE_BYTE_MAX));
+
+    ui_message_age->setText(
+        proto->fieldData(
+            StpProtocol::stp_message_age,
+            AbstractProtocol::FieldValue
+        ).toString());
+    ui_max_age->setText(
+        proto->fieldData(
+            StpProtocol::stp_max_age,
+            AbstractProtocol::FieldValue
+        ).toString());
+    ui_hello_time->setText(
+        proto->fieldData(
+            StpProtocol::stp_hello_time,
+            AbstractProtocol::FieldValue
+        ).toString());
+    ui_forward_delay->setText(
+        proto->fieldData(
+            StpProtocol::stp_forward_delay,
+            AbstractProtocol::FieldValue
+        ).toString());
+}
+
+void StpConfigForm::storeWidget(AbstractProtocol *proto)
+{
+    bool isOk;
+
+    proto->setFieldData(
+        StpProtocol::stp_protocol_id,
+        QString("%1").arg(
+            ui_protocol_id->text().toUInt(&isOk) & TWO_BYTE_MAX));
+
+    proto->setFieldData(
+        StpProtocol::stp_version_id,
+        ui_version_id->text());
+    proto->setFieldData(
+        StpProtocol::stp_bpdu_type,
+        ui_bpdu_type->text());
+
+    char flags = 0;
+    if (ui_flags_tc_check->isChecked()) flags = flags | ONE_BIT(BIT_0);
+    if (ui_flags_tca_check->isChecked()) flags = flags | ONE_BIT(BIT_7);
+    proto->setFieldData(StpProtocol::stp_flags, flags);
+
+    // root priority value stored as the first two bytes of stp_root_id 
+    // and the last 6 bytes are root MAC address (IEEE802.1D-2008)
+    quint64 rootIdPrio = ui_root_id_priority->text()
+        .toULongLong(&isOk) & TWO_BYTE_MAX;
+    quint64 rootId = hexStrToUInt64(
+        ui_root_id->text()) | rootIdPrio << 48;
+    proto->setFieldData(StpProtocol::stp_root_id, rootId);
+    
+    proto->setFieldData(
+        StpProtocol::stp_root_path_cost,
+        ui_root_path_cost->text());
+
+    // bridge priority value stored as the first two bytes of stp_bridge_id 
+    // and the last 6 bytes are bridge MAC address (IEEE802.1D-2008)
+    quint64 bridgeIdPrio = 
+        ui_bridge_id_priority->text().toULongLong(&isOk) & TWO_BYTE_MAX;    
+    quint64 bridgeId = 
+        hexStrToUInt64(ui_bridge_id->text()) | bridgeIdPrio << 48;
+    proto->setFieldData(StpProtocol::stp_bridge_id, bridgeId);
+
+    // port priority is a first byte of stp_port_id field
+    // and port ID is a second byte (IEEE802.1D-2008)
+    ushort portIdPrio = 
+        ui_port_id_priority->text().toUInt(&isOk, BASE_DEC) & ONE_BYTE_MAX;
+    ushort portId = 
+        ui_port_id_number->text().toUInt(&isOk, BASE_DEC) & ONE_BYTE_MAX;
+    proto->setFieldData(StpProtocol::stp_port_id, portIdPrio << 8 | portId);
+    // timers
+    proto->setFieldData(
+        StpProtocol::stp_message_age,
+        ui_message_age->text().toUInt(&isOk, BASE_DEC) & TWO_BYTE_MAX);
+    proto->setFieldData(
+        StpProtocol::stp_max_age,
+        QString("%1").arg(
+            ui_max_age->text().toUInt(&isOk, BASE_DEC) & TWO_BYTE_MAX));
+    proto->setFieldData(
+        StpProtocol::stp_hello_time,
+        QString("%1").arg(
+            ui_hello_time->text().toUInt(&isOk, BASE_DEC) & TWO_BYTE_MAX));
+    proto->setFieldData(
+        StpProtocol::stp_forward_delay,
+        QString("%1").arg(
+            ui_forward_delay->text().toUInt(&isOk, BASE_DEC) & TWO_BYTE_MAX));
+}
+
diff --git a/common/stpconfig.h b/common/stpconfig.h
new file mode 100644
index 0000000..f64b111
--- /dev/null
+++ b/common/stpconfig.h
@@ -0,0 +1,43 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#ifndef _STP_CONFIG_H
+#define _STP_CONFIG_H
+
+#include "abstractprotocolconfig.h"
+#include "ui_stp.h"
+
+class StpConfigForm :
+    public AbstractProtocolConfigForm,
+    private Ui::Stp
+{
+    Q_OBJECT
+public:
+    StpConfigForm(QWidget *parent = 0);
+    virtual ~StpConfigForm();
+
+    static StpConfigForm* createInstance();
+
+    virtual void loadWidget(AbstractProtocol *proto);
+    virtual void storeWidget(AbstractProtocol *proto);
+};
+
+#endif
diff --git a/common/stppdml.cpp b/common/stppdml.cpp
new file mode 100644
index 0000000..c2cffa7
--- /dev/null
+++ b/common/stppdml.cpp
@@ -0,0 +1,76 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#include "stppdml.h"
+
+#include "stp.pb.h"
+
+#define ROOT_IDENTIFIER_POS 22
+#define BRIDGE_IDENTIFIER_POS 34
+#define BASE_DEC 10
+#define BASE_HEX 16
+
+PdmlStpProtocol::PdmlStpProtocol()
+{
+    ostProtoId_ = OstProto::Protocol::kStpFieldNumber;
+
+    fieldMap_.insert("stp.protocol",
+                     OstProto::Stp::kProtocolIdFieldNumber);
+    fieldMap_.insert("stp.version",
+                     OstProto::Stp::kProtocolVersionIdFieldNumber);
+    fieldMap_.insert("stp.type", OstProto::Stp::kBpduTypeFieldNumber);
+    fieldMap_.insert("stp.flags", OstProto::Stp::kFlagsFieldNumber);
+    fieldMap_.insert("stp.root.cost", OstProto::Stp::kRootPathCostFieldNumber);
+    fieldMap_.insert("stp.port", OstProto::Stp::kPortIdFieldNumber);
+    fieldMap_.insert("stp.msg_age", OstProto::Stp::kMessageAgeFieldNumber);
+    fieldMap_.insert("stp.max_age", OstProto::Stp::kMaxAgeFieldNumber);
+    fieldMap_.insert("stp.hello", OstProto::Stp::kHelloTimeFieldNumber);
+    fieldMap_.insert("stp.forward", OstProto::Stp::kForwardDelayFieldNumber);
+}
+
+PdmlStpProtocol::~PdmlStpProtocol()
+{
+}
+
+PdmlProtocol* PdmlStpProtocol::createInstance()
+{
+    return new PdmlStpProtocol();
+}
+
+void PdmlStpProtocol::unknownFieldHandler(
+        QString name, int pos, int /*size*/,
+        const QXmlStreamAttributes &attributes, OstProto::Protocol *pbProto,
+        OstProto::Stream* /*stream*/)
+{
+    bool isOk;
+    OstProto::Stp *stp = pbProto->MutableExtension(OstProto::stp);
+    
+    if ((name == "") && (pos == ROOT_IDENTIFIER_POS))
+    {
+        stp->set_root_id(attributes.value("value").toString().
+                         toULongLong(&isOk, BASE_HEX));
+    }
+    if ((name == "") && (pos == BRIDGE_IDENTIFIER_POS))
+    {
+        stp->set_bridge_id(attributes.value("value").toString().
+                           toULongLong(&isOk, BASE_HEX));
+    }
+}
diff --git a/common/stppdml.h b/common/stppdml.h
new file mode 100644
index 0000000..5305e57
--- /dev/null
+++ b/common/stppdml.h
@@ -0,0 +1,42 @@
+/*
+Copyright (C) 2014 PLVision.
+
+This file is part of "Ostinato"
+
+This is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>
+
+This module is developed by PLVision  <developers@plvision.eu>
+*/
+
+#ifndef _STP_PDML_H
+#define _STP_PDML_H
+
+#include "pdmlprotocol.h"
+
+class PdmlStpProtocol : public PdmlProtocol
+{
+public:
+    virtual ~PdmlStpProtocol();
+
+    static PdmlProtocol *createInstance();
+
+    void unknownFieldHandler(QString name, int pos, int size,
+                             const QXmlStreamAttributes &attributes,
+                             OstProto::Protocol *pbProto, OstProto::Stream* stream);
+
+protected:
+    PdmlStpProtocol();
+};
+
+#endif