Questions tagged [udp]
UDP stands for User Datagram Protocol. With UDP applications can send messages (datagrams) to other hosts on a network without requiring prior communications to set up special transmission channels or data paths.
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Sending a UDP message stream - listener hanging after first receive
I'm attempting to use nc to send a stream of messages from one server to another using UDP. On the sending side, Centos 7.5, I'm doing the following:
for s in $( seq 1 20 )
do
echo "$(date +'%...
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Can't receive UDP data unless Wireshark is running
We have a computer system (Win10) that receives a variety of UDP data from a remote host at various rates (2-50Hz). The remote system is provided by our customer. While we're waiting for the customer ...
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Why is my UDP so slow?
I'm using Iperf on two VMs and when using TCP I find the performance is as follows:
notroot@ubuntu:~$ iperf -s
------------------------------------------------------------
Server listening on ...
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how to protect udp packets from packets loss?
when i tried to ping with mtr using udp pinging i gets packets loss from outside wan
the result of (mtr 8.8.8.8 -s 576 -n -u):
5. 149.6.154.169 ...
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Impact of Enabling UDP Checksum (IPv4) on the System
AFAIK, UDP checksum is an optional feature on IPv4.
I want to enable it on a gateway (IPv4), but I want to know if it has any negative impact on the system, e.g., increasing CPU utilization or ...
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What does it mean for a SOCKS5 proxy to have UDP enabled?
v2ray has options for enabling UDP for a socks5 server. What does this mean? How is it usable? How can I test the server to see if it is working correctly?
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how to get udp unicast to two hosts?
The two hosts need to have to same ip.
My solution at the moment is a port mirror, but the problem is as mentioned the duplicate of the ip address, I think. I couldn't find a way to disable the IP-...
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what is type of ICMP packets? TCP or UDP
The ping packet is a type of ICMP packet. Is there any relation between ICMP with TCP? In other words, can we guarantee their arrival in the network?
I want to know if ICMP packets in the network are ...
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UDP packets sent to wrong IP?
I have an IPTV box connected to my only router that assigned it a local IP 192.168.1.165.
I tapped the LAN cable right next to tv box and recorded traffic in Wireshark. There I saw a remote IP from my ...
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How to set different TTLHOP for TCP ports
We want to set sensitive TCP/UDP Ports at low TTL/HOP Leaving other ttl/hop at 128 default
data center = 3
Priv net = 8
Internet = 128 default
Ssh 22 = 8 (internal hop max)
Rdp 3389 = 8
Http 80 = 128 (...
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Constant receiving UDP packets from other local PC and firewall failed to block that specific IP address [duplicate]
Is it normal for a PC to keep sending out UDP packets to other local devices using random source ports?
In my case, I'm using Wireshark to monitor my own Windows PC network and I found there is one IP ...
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How to route all Ethernet traffic to a Serial port on a Linux system?
How can I route all Ethernet traffic on a Linux system to a Serial port and the opposite?
I want to convert from the first architecture to the second one, as shown in the picture:
picture
I monitored ...
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Routing from via remote bridge
Below is a diagram of my server and laptop, both inside the same LAN.
On the left, I have a server with a bridge ip (.128). The server also allocate another ip (.118) from the router but only ...
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SSH Tunnel + Socat UDP + Unicast + Multicast
I am trying to communicate from a machine LOCAL (sitting at home) with a scientific instrument (SCIENTIFIC, IP=192.168.1.109) which sits in a remote network along with a raspberry (SERVER).
SCIENTIFIC ...
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What is the difference between UDP hole punching and STUN? [closed]
As the title says, what is the difference between UDP hole punching and STUN?
Or is it the same?
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SSH Tunnel + Socat UDP Forwarding + multiple clients
I have an Ubuntu machine running a server daemon (Unity3d unet game server in this case) that is designed to communicate with clients solely via UDP. The clients are on Windows 7 and Windows 10. Due ...
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Protocol on Wireshark says LLC
enter image description here
A theoretical question may be.
I have created UDP traffic across my network involving client and Server. When i ping the server and monitor the data using wireshark, it ...
CommunityBot
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Chrome reports UDP port blocked but netcat can connect
I am using Chrome browser 84.0.4147.89 (64-bit) and when I run the Chrome Connectivity Diagnostics I get the following error log for UDP port 19302-19309.
SUMMARY
Test Name: Hangouts Connectivity ...
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WireGuard blocked - apparently a wider UDP issue
WireGuard is refusing to connect, I've tried running it on 2 different VPS providers (with my PC as the client) and it just doesn't work.
There are some commonalities which I noticed:
On both ...
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buffer deadlock prevented error from RTSP streaming over UDP
I have an issue to view RTSP streaming over UDP in the open VPN connection.
Our project is to integrate 360 degree IP camera in unity system. And we want to get the UDP streaming rather than TCP to ...
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How to ensure mobile-PC discovery in LAN?
I am developing a game that uses a PC as a monitor and a mobile phone as a gesture detector. Both devices communicate using UDP on the same local network (mostly Wi-Fi).
First, the PC creates a ...
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How to detect if network is dropping UDP packets?
I'm got a video streaming application that runs fine in my office but fails miserably at the customer location. The symptom is that every couple of seconds, I stop receiving UDP packets for 2 seconds, ...
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UDP packet and firewall
I notice when I send udp packets from computer A to computer B,
B can receive the upd packets correctly
but if I send udp packets from computer B to computer A
the udp packets are not received
A and ...
CommunityBot
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Linux SOCKS5 tunneling not working with udp traffic
I am using the command ssh -N -D 0.0.0.0:1080 localhost which works perfectly fine for my web browser, but when I try and tunnel a UDP traffic application it doesn't work.
I thought that socks5 ...
CommunityBot
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Displaying UDP Multicast Rawvideo Stream
I have a problem while trying to capture the raw video over UDP.
In my setup, I stream the webcam with FFmpeg (command line) via UDP, on the client side I use Java OpenCV, the capture line; ...
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VLC 3 can not play certain UDP streams
I have a stream on this address udp://@225.225.225.225:3002 and VLC 2.2.6 plays it perfectly, but on VLC 3.0.0 it can't be played. Are there any limitations for UDP on VLC 3.0.0? Are there any options ...
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How does DHCP OFFER broadcast work?
I am trying to understand the concept of DHCP relay agents and was reading this article. In section 3.2, talking about DHCP OFFER, it mentions that the DHCP relay agent replaces the destination ip to ...
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What address type do DNS queries use?
I was reading this thread and it was mentioned that DNS servers use anycast address. I have also heard that there is something called Unicast DNS as well.
So, my question is what type of addresses ...
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Is UDP full duplex or half duplex?
Can someone tell me if UDP is simplex/half duplex/full duplex?
I read conflicting answers here and here.
Would be great if someone can clarify this for me.
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How does DHCP handle multiple scopes in the same subnet
We are studying DHCP in our networking class and I have a Virtual Box in which I have set up 2 VMs - one of them is a Windows server and other is a Windows 10 workstation.
I have added the DHCP ...
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Why do most application protocols have two ports assigned?
So I am trying to learn about the application layer in the OSI model and when I go to the IANA website, I notice that most of the well known protocols have same port assigned for TCP and UDP.
For ...
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How to stream captured packets via UDP? tcpdump or other tool
I want to capture traffic or router and send it to remote host via tzcp or other udp proto.
How to stream captured packets via UDP? tcpdump or other tool
Use case:
Linux box connected to internet ...
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Getting a UDP-only VPN to work over TCP
For a project of mine, I'm searching for possibilities to have a UDP-only VPN working over TCP (preferably on port 443 or 80). I have found the following while doing some research:
This is possible ...
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/etc/nfs.conf equivalent for Debian/Ubuntu
What is the reason for /etc/nfs.conf not in Debian/Ubuntu?
There are /etc/default/nfs-kernel-server and /etc/default/nfs-common, but they aren't the same. They're used by /usr/lib/systemd/scripts/nfs-...
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FFMPEG: How do I output appended log files for Audio (silencedetect) and Video (blackdetect) Monitoring of a UDP Stream (not an MP4 file)
I am outputting log files for both audio and video monitoring for a UDP stream showing silencedetect and blackdetect. I have working code for both however I can't seem to get grep to filter only ...
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using udpcast over the internet
can I use udpcast-receiver to send file from my office in one country to a different branch located in another country? if so what options should I use? I tried nc - netcat with tcp it works but with ...
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How to remotely tell a Mac to sleep without using SSH?
I am needing assistance in getting a Mac to go to sleep without the usage of SSH. Almost any other method is acceptable.
Backstory: Product Salesman and Project Manger sold a thing without asking ...
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Udp packages bigger than 1472 are not being received
I have a c# client app. It sends data to my server using UDP.
However, this stops working after I upgrade to Windows 2019 Server.
the reason it stopped working is contained in this link:
https://...
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Need to Specify source for UDP video stream, what is the syntax?
I am trying to add to my IPTV box a m3u list with UDP streams but I have to specify the source IP in order for it to run. With VLC it works with this syntax:
udp://[sourceIP]:2000@[MulticatsIP]:2000
...
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What is corel doing on my udp connections for Chrome?
I have a weird mc.corel.com address lingering in Chrome and some parts of svchost processes, what is going on?
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Convert Received TCP packets to UDP and forward those packet
I have a service that listens on a TCP port and communicates with a peripheral. I'd like to forward the received packets by the service through UDP to an another computer. I don't need handshake with ...
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linux nc (netcat) UDP Connection refused
I faced with some strange nc behavior. It works well with TCP when on one host I do:
nc -tlp 31337
and on the other one:
nc 14.0.0.1 31337
So there can be some data exchange.
But when I do:
nc -...
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UDP IP Spoofing
I have a Ubuntu VPS in Singapore region and I have players who are going to play in my Indian Tournament.
My Indian server accepts only Indian traffic to protect from DDoS.
My players want to play ...
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Linux Redhat 7.1 UDP requests displaying in command line
I'm unfamiliar with Linux server administration and I am trying to disable firewall log messages appearing in the console, the version of Linux is RedHat Enterprise 7.1. I would like to know a command ...
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ffmpeg - copy http stream to multicast udp stream
i try to "copy" many tvheadend http streams to multicast udp streams
the result should contain all streams:
video, audio's and subtitels (especially epg)
...and at best without transcoding
my ...
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Linux - Can I Duplicate, send, then and Deduplicate UDP packets?
I am transmitting UDP data across 2 Linux (Intel) based routers, and I am experiencing low levels of packet loss which are interfering with the application.
Is there a way (ideally, but not ...
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Internet goes down when I connect the UDP Streaming into the Switch
Team,
When I connect the PC-1 ( within the same LAN) I have internet Drop issue.
The IP address of the PC-1 is
IP (192.168.86.119)
Subnet Mask (255.255.255.0)
Multicast UDP (238.1.1.1) ...
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Receive UDP packets from multiple broadcast servers
I have two sensors which broadcast their data using UDP. I configured them to use different ports.
If I connect only one sensor, I receive the packets using nc -ul port without any trouble.
If I ...
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UDP between A and B only works if B sends packet first
I have two separate linux computers, A and B, that need to communicate via UDP on port 3000. They are each behind a different router, and I have port forwarding rules set up on each router.
For some ...
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Why does Docker require udp ports to function - Can I disable this?
I came across strange behaviour with docker, where I tried to block all external UDP incoming & outgoing connections except for DNS (see mac pf config below) which breaks my docker containers.
...
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