Update README and add contrib dir

contrib/ethernet/model/ethernet-header2.h

@@ -0,0 +1,86 @@
+#ifndef ETHERNET_HEADER2_H
+#define ETHERNET_HEADER2_H
+
+#include "ns3/header.h"
+#include "ns3/mac48-address.h"
+
+namespace ns3
+{
+  /**
+   * \ingroup ethernet
+   * \brief Packet header for Ethernet
+   *
+   * This class can be used to add a header to Ethernet packet.
+   */
+
+class EthernetHeader2 : public Header
+{
+  public:
+    /**
+     * \brief Construct a Ethernet header.
+     */
+    EthernetHeader2();
+
+    /**
+     * \brief Destroy a Ethernet header.
+     */
+    ~EthernetHeader2() override;
+
+    /**
+     * \brief Get the TypeId
+     *
+     * \return The TypeId for this class
+     */
+    static TypeId GetTypeId();
+
+    /**
+     * \brief Get the TypeId of the instance
+     *
+     * \return The TypeId for this instance
+     */
+    TypeId GetInstanceTypeId() const override;
+
+    void Print(std::ostream& os) const override;
+    void Serialize(Buffer::Iterator start) const override;
+    uint32_t Deserialize(Buffer::Iterator start) override;
+    uint32_t GetSerializedSize() const override;
+
+    void SetDest(Mac48Address addr);
+    Mac48Address GetDest();
+    void SetSrc(Mac48Address addr);
+    Mac48Address GetSrc();
+    uint8_t GetPcp();
+    uint8_t GetDei();
+    uint16_t GetVid();
+    void SetEthertype(uint16_t ethertype);
+    uint16_t GetEthertype();
+
+    void SetVlanTag(uint8_t pcp, uint8_t dei, uint16_t vid);
+    void SetRedundancyTag(uint16_t seqNum);
+    uint16_t RemoveRedundancyTag();
+
+
+  private:
+    Mac48Address m_dest;
+    Mac48Address m_src;
+
+    //QTag (VlanTag, RedundancyTag ...)
+    enum TagType
+    {
+      VLAN,
+      REDUNDANCY,
+    };
+    struct Qtag
+    {
+        uint16_t TPID;          //Tag Protocol Identifier
+        uint32_t TCI;           //Tag Control Information
+        TagType Type;
+    };
+
+    std::vector<Qtag> m_QTagList;
+
+    uint16_t m_ethertype;
+};
+
+} // namespace eden
+#endif /* ETHERNET_HEADER2_H */