Why my laptop sends ARP request to itself ?

Posted by user58859 on Server Fault See other posts from Server Fault or by user58859
Published on 2011-01-07T13:47:41Z Indexed on 2011/01/07 13:55 UTC
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I have just started to learn about protocols. While studying the packets in wireshark, I came across a ARP request sent by my machine to my own IP. Here is the details of the packet :

  No.     Time        Source                Destination           Protocol Info
     15 1.463563    IntelCor_aa:aa:aa     Broadcast             ARP      Who has 192.168.1.34?  Tell 0.0.0.0

Frame 15: 42 bytes on wire (336 bits), 42 bytes captured (336 bits)
    Arrival Time: Jan  7, 2011 18:51:43.886089000 India Standard Time
    Epoch Time: 1294406503.886089000 seconds
    [Time delta from previous captured frame: 0.123389000 seconds]
    [Time delta from previous displayed frame: 0.123389000 seconds]
    [Time since reference or first frame: 1.463563000 seconds]
    Frame Number: 15
    Frame Length: 42 bytes (336 bits)
    Capture Length: 42 bytes (336 bits)
    [Frame is marked: False]
    [Frame is ignored: False]
    [Protocols in frame: eth:arp]
    [Coloring Rule Name: ARP]
    [Coloring Rule String: arp]
Ethernet II, Src: IntelCor_aa:aa:aa (aa:aa:aa:aa:aa:aa), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
    Destination: Broadcast (ff:ff:ff:ff:ff:ff)
        Address: Broadcast (ff:ff:ff:ff:ff:ff)
        .... ...1 .... .... .... .... = IG bit: Group address (multicast/broadcast)
        .... ..1. .... .... .... .... = LG bit: Locally administered address (this is NOT the factory default)
    Source: IntelCor_aa:aa:aa (aa:aa:aa:aa:aa:aa)
        Address: IntelCor_aa:aa:aa (aa:aa:aa:aa:aa:aa)
        .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
        .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
    Type: ARP (0x0806)
Address Resolution Protocol (request)
    Hardware type: Ethernet (0x0001)
    Protocol type: IP (0x0800)
    Hardware size: 6
    Protocol size: 4
    Opcode: request (0x0001)
    [Is gratuitous: False]
    Sender MAC address: IntelCor_aa:aa:aa (aa:aa:aa:aa:aa:aa)
    Sender IP address: 0.0.0.0 (0.0.0.0)
    Target MAC address: 00:00:00_00:00:00 (00:00:00:00:00:00)
    Target IP address: 192.168.1.34 (192.168.1.34)

Here the sender's mac address is mine(Here I have hiden my mac address). target IP is mine. Why my machine is sending ARP request to itself? I found 3 packets of this type. There was no ARP reply for these packets. Can anybody explain me why it is? (My operating system is windows-7. I am directly connected to a wifi modem. I got these packets as soon as I started my connection.)

I want one suggestion also. many places I read that RFC's are enough for study about protocols. I studied the RFC 826 on ARP. I personally feel that is not enough at all. Any suggestion regarding this? Is there more then 1 RFC for a protocol? I want to study about the protocols in very detail. Can anybody guide me for this? Thanks in advance.

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