Questions tagged [tcpip]

Transmission Control Protocol (TCP) and Internet Protocol (IP) provide end-to-end connectivity specifying how data should be formatted, addressed, transmitted, routed and received at the destination.

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What are CLOSE_WAIT and TIME_WAIT states?

When I do netstat -a on my Windows machine, I get a listing of the ports with one of the four states: - LISTENING - CLOSE_WAIT - TIME_WAIT - ESTABLISHED What do CLOSE_WAIT and TIME_WAIT mean/indicate?
Lazer
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Is there any benefit to using IPv6 on my home network?

I know that IPv6 is the future because there is only 4 billion IPv4 address, but on a home network, you are not going to have 4 billion users. So are there any other benefits that would make IPv6 on a home network better than using IPv4?
Macha
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Why are home networks prefixed with 192.168?

Why are home networks prefixed with 192.168 ? Why those numbers? For some historical reasons?
alex
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How to find the MAC address of a remote computer?

I know the IP address of a host on my own LAN. Using that, how can I find its MAC address (without having to physically access it)?
Frederick
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What does it mean to have a subnet mask /32?

I see in this question, the routing table has: 192.168.1.1/32 link#4 UCS 2 0 en0 openwrt.lan 46:94:fc:63:fc:7 UHLWIir 11 3610 en0 1200 192.168.1.125/32 link#4 UCS …
Number945
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Why is Windows' default IP address 169.xx.xx.xx?

My Windows system got an 169.xx.xx.xx IP address the other day, and I fixed the issue, but why did Microsoft chose this address as the default? Why not 1.xx.xx.xx or 255.xx.xx.xx? Did one guy at Microsoft say Hey, pick a number 1 to 255....who…
Adam
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Why is it bad to have open ports?

Here's something that has always baffled me. Why is it bad to have open ports on your computer? Assuming you don't have a virus on your computer or some other program listening to a port that may actually do something why does it matter if a port is…
aireq
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How do I see which processes have open TCP/IP ports in Mac OS X?

How do I see which processes have open TCP/IP ports in Mac OS X?
yazz.com
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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?
Lydon Ch
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what is TCP Half Open Connection and TCP half closed connection

I am trying to understand what is the difference between TCP Half Open Connection and TCP Half closed connection can any one tell what exactly are they?
Registered User
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How to kill a particular tcp connection in windows?

On Linux we can kill an Established TCP Connection using tcpkill command. For example, to drop all connection to/from a particular IP: tcpkill host ipaddr Or similary to kill all connection using port 21 at ethernet-1, by: tcpkill -i eth1…
Johnydep
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What's the difference between a TCP segment and a TCP packet?

Is a TCP segment not part of a TCP packet? Here's what I've read: A segment is a piece of application data chopped into a transportable size by TCP and wrapped with a TCP header Isn't the TCP header itself made up of segments?
use753231
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How to tell what MTU is being used in Windows XP

I'm suffering from a really weird problem where I randomly get "The connection to the server was reset" errors when trying to access web pages (HTTP error 12031 according to the Windows network diagnostic tool) - this happens regardless of whether…
andygeers
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Is your MAC address revealed when you hit up a website?

When you hit up a site, such as cnn.com, does the TCP/IP packet contain the MAC address of your network card? Could cnn.com theoretically record my MAC address?
AngryHacker
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Is there a hard limit of 65536 open TCP connections per IP address on linux?

Is there a hard limit of 65536 open TCP connections per IP address on linux? I read somewhere that there was, but someone is asking for confirmation and i just can't find it. I seem to remember it was something about the file descriptors being a 16…
Chris
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