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dannagle / PacketSender

Network utility for sending / receiving TCP, UDP, SSL, HTTP
https://packetsender.com
GNU General Public License v2.0
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[BUG] 0 and 1 Length ACK UDP packets not showing up in log #334

Open jalius opened 1 year ago

jalius commented 1 year ago

What OS and Version?

Windows 11 V 8.4.3 Binary

Description of issue

The log isn't receiving any 1 length or 0 length UDP packets. These packets are supposed to be responses like ACK, but they don't show up in the log. Wireshark does show the packets.

dannagle commented 1 year ago

This is by design. Packet Sender only shows the data because it lets the OS handle TCP session management.

jalius commented 11 months ago

This is by design. Packet Sender only shows the data because it lets the OS handle TCP session management.

Hi. Do you mind elaborating on this? I'm trying to implement UDP acknowledge but I think I'm missing something fundamental about networking.

dannagle commented 11 months ago

UDP does not use sessions. There are no acknowledgements unless you send that yourself in your code.

Since every UDP packet is complete, Packet Sender does not apply any filtering to UDP.

Here is a screenshot of a zero-data packet captured by Packet Sender:

image

You may want to set up a loopback test using 2 Packet Senders to help your understanding of what is happening. Take a look at this screenshot as a guide on how you can set that up: https://github.com/dannagle/PacketSender/issues/172#issuecomment-580263514 . For your test, use "UDP" instead of TCP.