UDP (User Datagram Protocol) is a simple connectionless transmission model formally defined in RFC 768.
Questions tagged [udp]
92 questions
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Can I use transport mode in IPsec if I tunnel via UDP?
Can I use tranport mode (instead of tunnel mode) in IPsec if I tunnel a VPN via UDP? I don't see why the header (that sets the protocol and port) needs to be encrypted in my case (I suspect it would be dropped if the firewall cannot see it as UDP…
Skaperen
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UDP-Only Linux Dedicated Server?
I am running my own small UDP linux service on a dedicated server. my service responds to single-package requests with single-package responses. I don't want this server to do anything else. I don't want it to access or serve the web, allow…
ivo Welch
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How to ensure security between devices from different manufacturers over multicast
I'm involved in the design of a protocol that allows different manufacturers to share data amongst their products. The protocol uses multicast over Ethernet so any device can join. Note that it's very likely there won't be an internet connection on…
parsley72
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How to prevent outgoing UDP attacks?
My server has been the target from hackers 3 times in the last month, and the attack seem to follow the same pattern. The attack another site from my server using UDP connection. The report from my ISP is the following:
19 Dec 2014 21:45:41:202 GMT …
jchatard
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Outgoing messages while under massive denial-of-service attack
As I understand it, there is no internet protocol that provides true broadcast like in say a card game or a partially synchronous network assumption. How close can internet protocols come though?
We've many parties playing some card game. Alice…
Jeff Burdges
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How Should Multiple Checksums Be Performed On the Same Data?
I am using CRC32 to verify the integrity of received UDP packets. Along with the generator polynomial, the sender will also specify how many checksums to perform on the sent data, as well as what iteration to start at in its body. How should this be…
Justin Marinelli
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What is the most powerful type of DDOS/DOS attack?
What I mean is what protocol are best to DOS something like TCP, UDP, HTTP?
user13254086
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UDP amplification: length(response_packet) < length(request_packet)
I was researching the GitHub DDoS attack of 2018, in which memcached UDP amplification was used. I noticed that a GitHub blog post referenced a CloudFlare post which described memcached-based UDP amplification attacks in general. At one point,…
CharlieBucket
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Why do processes on servers have socket types associated to the port number?
Why do some servers have TCP/UDP alongside the port they're listening to. To my understanding TCP and UDP are socket layers, they're methods of determining how the traffic is being sent over the network, so why would this be relevant when sending a…
J.Doe
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is -nU an option with nmap?
My coworkers seem to have -nU (no udp) as an option for their nmap scripts but I've never seen this in use and when I try to use this option with nmap, it does not work. I thought no udp was enabled by default and -sU had to be used for udp to be…
UCProgrammer
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Machine reaching out to Microsoft IP address using NBTstat command
I have limited logs for this event but the IPS says its a NBTstat query outbound over UDP port 137 to a Microsoft owned IP address.
Should UDP 137 ever reach out externally?
This is about all the information I have as its very limited access to…
Kajunga
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Why is spoofing allowed in reputed VPS services?
I just learned about IP spoofing and so I set up VMs and sent spoofed UDP packets (8.8.8.8, Facebook's IP, Twitter's IP) to myself (home PC and mobile) from well-reputed VPS providers like AWS, Softlayer, Intellectica Systems, etc. and I was able to…
Al-Alamin
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Spoofing an IP/MAC address to avoid ICMP Destination Unreachable being sent back
As far as I understand UDP flooding the idea is to send UDP packets across all ports from e.g. Alice to Bob, and get Bob's machine to check who listens to certain ports and generate many ICMP destination unreachable packets to be sent back (+ Bob's…
chao
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No authentication, AES encrypted JSON over UDP
I was recently assigned the task of testing a new hardware device which communicates with a JSON API over UDP.
For some reason or another, it was decided that AES-CBC-128 should be used to encrypt the traffic. I believe this was to prevent someone…
Stereoblind
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UDP replay "attack"
Suppose that there is a client-server application using UDP and you have full control over client. The task is to automate few known actions on the client and make them very fast.(Possibly bypass client application completely).So my question is:
Is…
dev034
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