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?
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1answer
613 views

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 ...
1
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2answers
767 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 ...
1
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2answers
159 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 ...
3
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1answer
429 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. ...
0
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2answers
852 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
612 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 ...
0
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1answer
593 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 ...
2
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4answers
2k views

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?
0
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1answer
624 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
3
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2answers
1k views

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' ...
5
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1answer
11k views

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 ...
21
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5answers
6k views

Why are home networks prefixed with 192.168?

Why are home networks prefixed with 192.168 ? Why those numbers? For some historical reasons?
7
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12answers
5k views

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 ...
4
votes
3answers
855 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 ...
2
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3answers
2k views

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 ...
2
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2answers
6k views

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 ...
5
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2answers
2k views

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?
0
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5answers
719 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 ...
3
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4answers
963 views

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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0answers
386 views

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
6k views

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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2answers
459 views

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 ...
2
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3answers
3k views

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 ...
0
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1answer
6k views

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?
0
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1answer
4k views

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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2answers
9k views

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?
6
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6answers
5k views

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 ...
0
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1answer
433 views

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?
7
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2answers
8k views

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 ...
5
votes
3answers
706 views

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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1answer
545 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 ...
9
votes
2answers
4k views

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?
4
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1answer
4k views

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
129 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 ...
3
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3answers
8k 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?
4
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1answer
379 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 ...
0
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1answer
91 views

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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1answer
1k views

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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3answers
1k views

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
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3answers
2k views

Switching between DNS addresses easily

Sometimes I need to use preferred and alternate DNS server addresses, and sometimes I need Windows to obtain it automatically. The common approach to switch between those addresses is: Right click ...
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5answers
357 views

Only browser causes BSOD — all other TCP operations okay

A few weeks ago I started getting BSODs -- mostly in TCPIP.SYS, but occassionally Memory Parity. I had some viruses which are now all removed. I got new memory -- didn't fix it. Over time I was ...
5
votes
2answers
812 views

Poor TCP performance over single connection, but not over multiple?

On two separate Dell machines, I seem to be having an annoying performance problem when downloading over a single connection. The one I've just tested this all on is a Dell Dimension 3000, XP SP3, P4 ...
14
votes
7answers
14k views

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 ...
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2answers
1k views

Wireless network connection keep dropping

After reinstalling windows XP on my laptop, I've noticed that about ever 3 mins, my wireless network connection will disconnect and then reconnect. I found the following error in the system event ...
1
vote
3answers
717 views

OpenDNS name servers

I'm using the below open DNS name servers which I got from a friend. Are they trustable? 4.2.2.1, 4.2.2.2, 4.2.2.3, 4.2.2.4, 4.2.2.5, 4.2.2.6
2
votes
1answer
1k views

Smokeping monitoring IP address and port

I have successfully install smokeping on my Ubuntu Karmic machine and am monitoring servers. I need to be able to monitor an IP address and a port, can someone tell me how I do that? I looked into ...
2
votes
6answers
4k views

Why does my XP system lose TCP/IP connectivity every night around 3 AM?

Every night around 3 AM from the eventlog (Outlook complains it can't get to the exchange server) I lose all TCP/IP connectivity from my desktop. Other systems on the network still function, as well ...
1
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4answers
799 views

A can ping B, B can ping C but A cant ping C. How do i connect A to C (ethernet)?

I have a computer at home with ip 192.168.221.xxx I have another computer at work that I can ping and it has 2 ip addresses: 192.168.1.xxx and 192.168.0.xxx. Those last 2 addresses have the same ...
2
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3answers
4k views

Is there a command line way to show the outward-facing IP address for my machine?

Is there a command line way to show the outward-facing IP address for my machine?