networking - How to generate UDP packet

06
2013-08
  • portoalet

    I want to generate UDP packet to test a program, something equivalent to using telnet to test TCP port (Can telnet generate UDP packet?)

    How can I do this?

    • Answers
  • quack quixote

    One word: Netcat

    Netcat is the go-to tool for this sort of thing.

    You can thrash whatever port you choose with udp packets with something like:

    nc -u host.example.com 53 << /dev/random

    (53 is your port number)

    Or you can send an actual file, or tell it to bind that port and listen as a service, or whatever you like.


    • Related Question

    networking - What does this UDP Packet mean?
  • Questioner

    I'm total newbie at tcp/ip and I was experimenting with Wireshark.

    What this mean:

    1824    578.194204  xxx.xxx.xxx.xxx yyy.yyy.yyy.yyy UDP Source port: 17500  Destination port: 17500

    In data I can see that my user pc name is sent (happily it's a generic name): does this mean someone is trying to hack my pc ?

    Update I have another one which is port 56712 and yyy.yyy.yyy.yyy is the ip of someone with the same provider as me. Isn't this weird (OK I'm paranoïd :)) ?


    • Related Answers
  • Mokubai

    Do you use Dropbox or similar software? Apparently the port you listed is used by Dropbox...

    http://isc.sans.org/port.html?port=17500

    Edit: Looks like it could be someone elses machine with Dropbox installed looking for "Lansync Compatible clients" http://forums.dropbox.com/topic.php?id=16253

  • dbasnett

    If you do have dropbox this link shows how to turn that off if that is what you want

    DropBox Forum