1. ARP Request/Reply Can we modify our previous device-driver so it will allow us to send and receive ‘raw’ packets?

2. ARP packet (Type 0x0806) Ethernet Header ARP Protocol Header Data (optional) 14 bytes 28 bytes

3. ARP packet-header Hardware TypeProtocol Type Hardware Length Operation (1=request, 2=reply) Sender Hardware Address (upper 4 octets) Sender Protocol Address (LSW) Sender Hardware Address (lower 2 octets) Sender Protocol Address (MSW) Target Hardware Address (lower 4 octets) Protocol Length Target Hardware Address (upper 2 octets) 32 bits For Ethernet: Hardware Type = 0x0001, Hardware Length = 0x06 For Internet: Protocol Type = 0x0800, Protocol Length = 0x04 Target Protocol Address

4. ARP request and reply