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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Program that listens to a TCP/IP port for text and execute (emulate) a key stroke on keyboard?

I am looking for a program to be run on Windows Vista that would listens to a TCP/IP port and execute or emulate a keyboard's key stroke (or a combination of keystrokes, such as Ctrl + D). It's like ...
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3answers
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Why a single(?) TCP packet gets split to multiple PDU units here?

Pic related: Why those segments are marked as separate packets (all Ack, Seq=509)? Why did a packet get split?
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Is the MAC address used on the DLL layer unique throughout the world for a device, lets say this computer?

Is the MAC address used on the DLL layer unique throughout the world for a device, lets say this computer?
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Difference between localhost and the ip address

If bind a socket in Python to localhost,8200 this is accessible via http://localhost:8200/. but not http://x.x.x.x:8200/ If bind a socket in Python to x.x.x.x,8200, machinename,8200 this is ...
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Windows 7: How to solve IPv6 “No network access” problem?

I'm tearing my hair out on this one. Basically I need IPv6 to work on a Windows 7 (Home Premium) Dell laptop and it isn't. I have the wireless networking all working but if I click on the wireless ...
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2answers
726 views

Is `ip` to supersede `ifconfig`

A friend of mine said that ip is supposed to be the successor of ifconfig and iwconfig — yet I found no Wikipedia article about it and have never seen anyone mention or recommend it online even though ...
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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)?
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1answer
261 views

NIC recommendation and advice for building network packet capture PC

Greetings, I am trying to build a dedicated PC for capturing and recording network packets in a heavily loaded test environment. I am expecting total data loads to be between 150-200Mbps and want to ...
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4answers
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How do you block specific urls and not entire domain

I want block a URL on specific computer, in this case www.google.com/reader but i not want to block the entire domain of google. It is for my work machine as I don't seem to have enough self control ...
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4answers
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How do I rebuild the TCP/IP stack on XP?

Consider a computer has been hit with a spyware bomb and it has destroyed the internet connectivity in almost every way. (no ethernet, wireless, or dial-up) Because it would take forever to backup ...
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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?
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Fix Internet connection stalls (packets getting stuck somewhere?)

The wireless AP I've been using has glitched out and the two symptoms are the DHCP server no longer working, and random stalls in the connection. I can't reboot it, so I've been trying to solve the ...
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785 views

IP Forwarding on the same subnet

So, my situation is, I have a PC with two network cards, one is a physical ethernet adapter, the other a wireless adapter. Both network cards are on the same subnet. I need to be able to forward IP ...
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2answers
161 views

Route Local Network through Server?

This may or may not be an easy question, as I'm somewhat uninformed in the networking side of computer science. I own a rented server with a static ip address. Is there a way that I can forward ...
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1answer
436 views

why is my computer connecting to skynet? is it a virus or other type of malware?

i recently ran a "netstat" command on my windows xp system, and saw some connections to "Iron.Skynet". well Iron is my Computers Name, but ive not come across the name "Skynet" on my system before. ...
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887 views

Changing MAC address in a linux machine (fedora 8)

I am doing a test on MAC learning and for that ,I need to change my MAC address of linux machine while the interface is UP. To be more clear, consider eth1 in a fedora core 8 machine. And while the ...
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3answers
621 views

How to assign IP address to computer on XP Pro network

If I go into TCP/IP settings to manually set an IP address for an XP machine, what should be set for: Subnet mask Default gateway What would happen if I set an IP address that is already assigned ...
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1answer
602 views

Can ping server but no telnet or www

I have a NAS (Iomega home media 1TB) connected to a router with a 1Gb ethernet cable. Occasionally I lose access to it; when this happens I can still ping it by it's static IP or scan it with Nmap but ...
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4answers
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Do you get given your own IP address on dialup?

Do you get given your own IP address on dialup? I am trying to test remote connections from outside my LAN. Will I be given an IP address that I can use for remote desktop and assistance?
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644 views

Win 2k3 Connections Limit per ip:port

I want to limit connections number per ip on specific port. Should I use some firewall or anything else? Advice please. P.S. Port doesn't have to be port 80, or 3389. It can be any port
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2answers
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What are ping packets made of?

What exactly are in the packets that are sent via the ping command? I was reading a Wikipedia article about magic numbers and saw this: DHCP packets use a "magic cookie" value of '63 82 53 63' ...
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1answer
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Force socket close

Is it possible to close an established socket connection in Windows "manually" (e.g. using a command prompt tool)? I have several open sockets connected to a listening server, I can see them using ...
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5answers
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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?
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Why is IP to MAC address translation needed?

On networks that use the TCP/IP protocol, why is the IP address translated into a MAC address? I mean, when every device knows its IP, why further use the MAC address and not use the IP number as ...
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3answers
874 views

How to get started with TCP/IP v6?

Now and then there is "news" about that the IP numbers will run out in X years, and we must change to TCP/IP v6... And even though this crisis never really happens it has waken a question, how do ...
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Access Windows from Mac via Remote Dekstop Connection using hostname

I'm using Snow Leopard with Remote Desktop Connection attempting to access a Windows XP machine on a home network. If I specify the Windows PC's hostname it won't connect. Only by specifying the IP ...
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What does this UDP Packet mean?

I'm total newbie at tcp/ip and I was experimenting with Wireshark. What this mean: 1824 578.194204 xxx.xxx.xxx.xxx yyy.yyy.yyy.yyy UDP Source port: 17500 Destination port: 17500 In data I ...
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Is there a tool to modify HTTP packet on the fly?

Wireshark is good, but it doesn't allow you to change the content of the packet. Is there a tool to do this job?
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741 views

Too many connections to 212.192.255.240

Recently my Internet slowed down drastically. I downloaded a tool to see the TCP/IP connections from my Vista computer. I found that a lot of TCP/IP connections are being made to 212.192.255.240 ...
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4answers
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Is there any SMS/MMS server for LAN environment

I am looking for a solution to send SMS/MMS message to mobile device from desktop or browser in LAN environment. As such, it is most probably using TCP/IP protocol to transmit request/response. The ...
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How to choose which network connection provides the default gateway in Windows XP [duplicate]

Possible Duplicate: How can I change the binding order of network adapters in Windows 7? I have a laptop with an integrated NIC and a WiFi connection. Both the wired and wireless networks I ...
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7answers
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In linux, how can I get my IP address - ifconfig and ip addr show are not working

This should be simple, but the machines we ssh into don't seem to have the regular commands. Are there any other simple ways I can use to get my IP?
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Is it possible to know which process opened a connection in Windows?

With netstat -a I can see all connections from my machine to the MySQL Server. There is any way too see which process or executable is responsible for each connection? The only solution I found so ...
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How do the routers communicate with each other?

Let's say that i want make a request a to a web page which is hosted in Europe (i live in USA).My packets only consist the IP address of the web page, first the domain name to ip address ...
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1answer
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TCP/IP Forwarding in Windows Vista and Above

This is the way to do it on XP, but is it possible on Windows Vista and Above? If so how do you detect it? Is there a registry setting for it, or is there com dll or api for it?
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1answer
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Yahoo Messenger IP range

I use PeerBlock (former PeerGuardian) and, as a consequence, Yahoo Messenger (actually Pidgin) fails to connect every once in a while; PeerBlock reports the access being blocked because the ...
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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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Why is my router not routing?

Starting a week and half ago my router stopped working with my cable modem. I went to sleep with it working and woke up with it not. I swapped in another router and am still having issues; I was ...
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1answer
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Is it possible to just deny download from TCP/IP?

I want to deny my Internet connection's download properties for all ports. I mean I want to only allow upload. Is it possible?
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What is “Disable class based route addition” good for?

In the advanced TCP/IP settings of a VPN connection, i found a checkbox labeled with "Disable class based route addition". The checkbox is only enabled as long as "Use default gateway on remote ...
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Multiple home routers

Suppose I have the following configuration: Router A: WAN port connected to the Internet, LAN = 192.168.1.0/24 Computer A: Connected to router A as 192.168.1.101 Router B: WAN port connected to ...
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548 views

retransmission of lost TCP segment

What will happen in the following scenario (assume the connection is already established): (stack A) send 10 byte data (stack B) send ACK for 10 byte data (stack B) send 200 byte data (stack B) send ...
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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?
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1answer
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How to enable “packet forwarding” in OS X

How is it possible to enable packet forwarding in Mac OS X? Google gives me tons of hints for Windows and Linux but not for OS X.
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1answer
136 views

workstation 7 and host-only no connectivity

I have a WinXP 32 host (IBM T400) with VWware workstation 7 (7.0.1 build-227600) and some guest OS (Win xp, NT, etc.) I can ping from the host to guest OS and vice versa, but... every other ...
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5answers
10k views

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?
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1answer
396 views

Why does MacOSX try to resolve zero padded IP addresses as host names?

This one caused a friend some headache when setting up a switched internet connection which had zero padded IP addresses in the configuration paper like so: 192.168.019.254 No matter how he tried to ...
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1answer
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How would I do this in wireshark?

I have four packets captured in wireshark. ARP request and reply packets and ICMP packets. What field and values are used to identify the different packets carried by an ethernet frame?
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DHCP not working after NetBIOS over TCP/IP disabled

I want to disable the "NetBIOS over TCP/IP" device in the device manager to free port 445. But after doing that my Internet stops working. I'm connected to a WLan router using DHCP on WinXP, and it is ...
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IPv4 forward on windows?

Is there anything that can forward/redirect all incoming traffic to another ip. Basically I'm looking the windows equivalent of ip forwarding in linux. echo "1" > /proc/sys/net/ipv4/ip_foward