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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How to generate UDP packet

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?
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1answer
2k views

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 ...
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2answers
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what is type of ICMP packets? TCP or UDP

ping packets is a type of ICMP packets.Is there any relation between ICMP with TCP.In other can we guaranty their arrival in the network I want to know ICMP packets in the network is tcp or udp or ...
2
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1answer
126 views

How to monitor TCP and UDP port changes

I am running software on a server that may be turning off some ports and need to find out what it is. I have the ports I need to check. I just need to find out what is turning them off. How can I ...
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1answer
504 views

“udp relay” via openssh socks proxy

I'm trying to run a UDP based multiplayer game (dota 2) via the following chain dota2 (OS X)-> proxycap -> ssh tunnel -> home machine (OS X) -> internet The home machine is running the ...
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3answers
5k views

Proxifier that supports UDP?

Im looking for a proxifier that forces all Windows traffic through a specific proxy. I have my own server so I can ultimately configure any type of proxy (Socks, HTTPS, etc) so thats not a problem, ...
2
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2answers
4k views

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 ...
2
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3answers
684 views

Broadcast address in IPV4

I have a small network with the subnet mask 255.255.255.240 and the IP range is 192.168.2.1 - 192.168.2.12. From 192.168.2.1, I want to broadcast a packet. I don't want this packet to go anywhere ...
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1answer
259 views

Using and testing UDP data over the internet [duplicate]

I have a GSM modem that sends data via UDP (it appears) I have configured it to send all data to my public IP address over the internet but no data is arriving at my end so I need to troubleshoot. I ...
0
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1answer
97 views

Are all internet file downloads using FTP protocol?

I heard, FTP is used to transfer files over a network. Also heard that it uses TCP port 20 and 21. So TCP is connection oriented. We have acknowledgments. If the transmission is lost, we should be ...
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1answer
2k views

What range of UDP ports may rtsp use, to configure a firewall?

To allow incoming rtsp streams, I must open incoming TCP port 554. I must also open a range of UDP ports. 6970 through 6999, says http://comments.gmane.org/gmane.comp.security.shorewall/660 . At ...
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0answers
1k views

How to direct a UDP Packet through a vps tunnel?

How to direct a UDP Packet through a VPN Tunnel over a WAN? Have been trying to set up a instant messenger service though the office network and it dose not have UDP flooding or UDP broadcasting. ...
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1answer
357 views

IP checksum offload

I recently updated to Windows 8 and get alot of invalid packet transfers. It says "Ip checksum offload?" (Wireshark) and most of my packets get lost. The checksum is 0x00. I also updated my NIC ...
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1answer
598 views

How does a proxy know where to forward the requests to?

When a proxy receives a connection how does the proxy know where to forward the request to? For example in Java we can set a system property for proxy. So we set the IP of the proxy and the request is ...
0
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1answer
769 views

Are UDP packets firewall proof?

I have been testing this "bittorent sync" software (a peer to peer application) as an experiment. I decided to block the application using the Windows firewall on the computer that is running the ...
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1answer
150 views

Wake-On-LAN and Access Control List with Mac over Internet

I am researching the best way to wake my computer through a firewall over the internet remotely (the computer to be woken is a Mac). Through external research, I have seen that I should be able to ...
2
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2answers
4k views

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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1answer
1k views

Limit UDP outbound traffic to loopback (localhost) instead of eth0

Atm i'm testing it on Ubuntu Server at VMware Workstation + Windows 7 local host with bridged connection. Later this has to go to live server. I have VLC streaming video file on Ubuntu with cvlc ...
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1answer
2k views

netcat udp address already in use

I am trying get a response from the server by using the command echo 'my message' | nc -l -u 127.0.0.1 2947 But I get nc:Address already in use. for a response. How do find the reason for this ...
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0answers
144 views

Send data from file to local UDP port

I've got an application, A, that listens on a user-defined UDP port for a specific message that normally comes from another application, B. Application B has a tool that allows recording these ...
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1answer
59 views

TCP vs UDP Error-Checking

I've bounced upon two articles that describe in-depth on how TCP and UDP connections work. However there is some kind of inconsistency. Where one article tells me that UDP does no Error-Checking at ...
0
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2answers
107 views

Port forwarding beginner

I have been trying to set up port forwarding for the past 48 hours and I can't quite get it. I have used online port scanners to see what ports are open and they are saying none, not even the port I ...
0
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1answer
385 views

DNS: can't dig 8.8.8.8 directly

me@ubuntu:# dig @8.8.8.8 google.com ; <<>> DiG 9.9.2-P2 <<>> @8.8.8.8 google.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be ...
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0answers
1k views

FFmpeg/avconv and UDP - connect listener after sender?

I'm trying to troubleshoot a port binding issue in avconv/FFmpeg. I have two test commands; one which sends an audio stream over UDP: avconv -i test.wav ...
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3answers
285 views

UDP checksum inconsistency between sender and receiver

I want to write a program to generate udp checksum. to validate my progra, I need some real data. I send a udp packet from one machine to another machine, the packet can be correctly received by the ...
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1answer
2k views

vlc part of desktop streaming to <host>:<port>

With VLC, I wish to stream a portion of the desktop and send it to another host on my local area network. The capture seems to work, I see a correct portion of the desktop into the VLC server, but ...
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2answers
194 views

Is sending syslog events over udp secure?

I'm considering using a service from papertrailapp.com (other similar services are loggly and splunk), where you configure your syslog to echo events to it over udp. It involves adding this entry to ...
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3answers
399 views

How can I open a TCP/UDP connection on Linux?

I am looking for a simple command line tool to open TCP/UDP server/client on a desired port on a Linux machine. Are there any applications or commands that I can use to achieve this?
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1answer
2k views

Connecting Android via wifi to Wifly RN-XV RN-171 using Access Point (soft AP) mode not working

I hope somebody has encountered this problem and knows how to fix it. I purchased a Roving Networks RN-XV module to communicate directly with an Android device. I thought it would be perfect because ...
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1answer
831 views

How to get rid of UDP checksum error messages in virtual console?

Whenever I am streaming a video in the web browser, while connected to my school LAN via ethernet, and switch to the virtual console (ctrl-alt-f1) on Ubuntu, I get an error that looks like the ...
0
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1answer
107 views

My laptop can't find a device that is connected to a my router but my other laptop can find it

I have this device that uses port 80000 and UDP. It came with a program that communicates with it. However, my laptop (laptop A) can't find that device using the program. So I tested the program to my ...
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1answer
121 views

How to optimise a Motorola Wing 5.3 Access Point for UDP traffic

I have a motorola wing v 5.3 which I need to optmise for UDP traffic. I have some UDP packet loss and I think that if I change the AP configuration I would get a better result. Anyone has experience ...
0
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1answer
813 views

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 ...
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0answers
457 views

Dropbox LAN sync - hint for an IP address

In my work network UDP broadcast networks are isolated between the WiFi and wired channels, so LAN sync discovery does not work. Is there a way to explicitly tell Dropbox to try a specific IP address ...
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1answer
546 views

ffmpeg udp audio livestream

Having trouble getting the following command to stream audio through udp, is there a parameter missing? ffmpeg -f alsa -ac 1 -i hw:1 -ar 44100 -f mpegts udp://10.255.255.255:10000?pkt_size=1316 The ...
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0answers
181 views

UDP NAT punching for linksys wrt54g

I could not explain the strange NAT behavior, hope someone could help: I have a linksys wrt54g router at home. Client sends UDP keep alive packet from 192.168.1.20:16688 (nat outside public IP/port ...
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3answers
2k views

NAT and UDP replies

Sanity check please. If I send UDP packets from Machine A behind a NAT to Machine B's port N, where Machine B is outside the NAT (elsewhere on the Internet), can I reasonably expect that NAT to pass ...
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0answers
416 views

Routers and NAT hole punching? [closed]

I'm trying to understand why UDP hole punching works. Given peers A, B behind a NAT router and Server with port 80 open. A sends a packet to Server from port 1234. This causes the router to open a ...
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0answers
227 views

Artificial network delay tcp/udp (bigger ping) for defined application? (windows)

I have a game where people can easy detect who i am looking at my ping, i want to make my ping highter. How can i set network delay for all network connections for defined application?
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1answer
449 views

How to wrap an UDP connection to improve resistance agains packet loss?

Suppose there is UDP connection that does not expect much packet loss. Are there already tools that allow wrapping a UDP connection to gain more reliability at expence of bandwidth and overhead, for ...
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1answer
629 views

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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2answers
406 views

determine connections limit enforced by my ISP

I know my new ISP is enforcing a lot of different limitations. They refuse to say what are the limits. To determine bandwidth I can use sites like http://www.voiptest.org/ (BTW it shows me ~15% of ...
2
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0answers
237 views

Tunnelling TCP connection through NAT

My server is in my school's NAT and my desktop computer is in my home NAT. I want to SSH to my server from home. I normally used school's VPN, but recently for some reason I can't. So I'm looking for ...
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2answers
740 views

TCP/UDP hole punching from and to the same NAT network

I was wondering if tcp/udp hole punching would still work when you are in the same network (behind a NAT), and what the packet's path would be. What happens when using hole punching on the same ...
8
votes
2answers
764 views

Puzzling TCP performance over 3G / UMTS

I'm using 3G as my primary internet connection, and TCP over this thing is getting more puzzling every day. For example: Downloading from kernel.org is crazy fast: $wget ...
0
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0answers
339 views

What would cause different rates of packet loss between client and server in UDP?

If I've implemented a reliable UDP file transfer protocol and I have a file that deliberately drops a percentage of packets when I transmit, why would it be more evident that transmission time ...
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2answers
1k views

Kill UDP port that has no process?

My VPN client sometimes can't bind to the UDP port (500) it uses. It seems to leave behind a "bind" to port 500 on a previous run, even though it has quit. The port is reported as "already in ...
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2answers
11k views

How to stream my media via vlc using udp streaming method?

I would like to know how to stream my media via vlc using udp streaming method?
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0answers
2k views

RTP input stream on VLC

I'm trying to play on VLC a RTP input stream coming from the port 9954, UDP socket. So, I launch VLC on the console with this command: vlc -vvv rtp://:@9954. VLC appears, but no media is played. The ...
0
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2answers
848 views

Wake On Lan will not work no matter what

I have been having the most frustrating time trying to get my desktop computer to wake up from a magic packet. The worst part is, I am almost 100% sure that I have had it working on this computer in ...