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Questions tagged [udp]

For questions about User Datagram Protocol, a Transport Layer protocol.

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1answer
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UDP hole punching NAT port

I just read an article about the process of "punching holes" with the UDP protocol. I understand how it's done, but I have one last question to clear up things. We have the rendezvous server and ...
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1answer
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Traceroute UDP port question

I know, that traceroute uses UDP, and for destination port it starts with 33434. Then, with each next hop it increments the destination port number by 1. The questions is: why does traceroute need to ...
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4answers
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Why is a TCP Socket identified by a 4 tuple?

Newbie to networking here. I'm reading the Computer Networking (3rd edition) book, and in section 3.2 they are discussing multiplexing / demultiplexing for both UDP and TCP. In the UDP protocol, a ...
5
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1answer
1k views

What is the reason for the different order of the Source and Destination in a L2 header?

A TCP/UDP header (Layer 4) lists the Source Port, then the Destination Port: An IP header (Layer 3) lists the Source IP, then the Destination IP: An Ethernet header (L2) and a WiFi Header (L2) lists ...
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2answers
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How does a layer-2 switch work with UDP?

If UDP and/or TCP send packets via IP to an Internet Protocol Address, how can a layer-2 switch forward these? Is this possible or do you need a layer-3 switch?
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2answers
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Should I increase the timeout value for UDP on our VPN router-device?

We have a SonicWALL NSA 2400. We have numerous (100+) personnel in different offices in different physical locations that establish VPN sessions successfully every day. Some of these client computers ...
8
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4answers
22k views

How to know whether a protocol uses TCP or UDP

Well I know that might sound a stupid question and I believe that the most proper answer will be like I will be able to tell as my experience builds up and I learn more and more about the protocols. ...
6
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2answers
2k views

Why maximum length of IP, TCP, UDP packet is not suit?

From many tutorials, I get follow knowledge(maybe I'm misunderstood) : maximum of an Ethernet packet is about 1500 bytes. maximum of an IP packet is about 65535 bytes. maximum of a UDP packet is ...
6
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3answers
568 views

Is UDP Usage in Routing Information Protocol (RIP) a Secure Practice?

I know that UDP is a connectionless transport layer protocol. Since it is easy to fake your source IP and source Port in your headers, what keeps anyone from poisoning routing tables via RIP? It seems ...
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3answers
6k views

Why do i only see QUIC and not UDP during capture in wireshark?

I've been using wireshark and noticed that I no longer see UDP but QUIC, why is this the case?
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2answers
2k views

When is TFTP used? [closed]

It seems like a strange idea to transfer files using a connectionless protocol - so in what situation would you not care about if the entire file is delivered or not? I read somewhere that TFTP is ...