Questions tagged [ip]

The IP (internet protocol) is a protocol for transmitting data over packets ("datagrams"). It is the primary protocol of the Internet. "IP" may also refer to an IP address, the numerical address assigned to an IP-capable device.

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838
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3answers
164k views

Transatlantic ping faster than sending a pixel to the screen?

John Carmack tweeted, I can send an IP packet to Europe faster than I can send a pixel to the screen. How f’d up is that? And if this weren’t John Carmack, I’d file it under “the interwebs being ...
381
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4answers
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Why does pinging 192.168.072 (only 2 dots) return a response from 192.168.0.58?

I mistakenly missed the dot off of an IP address and typed in 192.168.072. To my surprise I connected to a machine at 192.168.0.58 If I ping 192.168.072 I get responses from 192.168.0.58. Why is ...
248
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9answers
616k views

How can I list all IPs in the connected network, through Terminal preferably?

Using Ubuntu 10.10 command line, how can I list all IPs connected to my home network? Ideally, it needs to be a CLI command as I will be running it from C++.
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13answers
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What is the exact use of a MAC address?

I understand that IP addresses are hierarchical, so that routers throughout the internet know which direction to forward a packet. With MAC addresses, there is no hierarchy, and thus packet forwarding ...
120
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7answers
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Why can't I email myself at: MyEmail@74.125.235.55?

I opened cmd and typed ping gmail.com. It shows me: C:\Windows\system32>ping gmail.com Pinging gmail.com [74.125.235.55] with 32 bytes of data: Reply from 74.125.235.55: bytes=32 time=6ms TTL=56 ...
112
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14answers
16k views

Must TCP use IP?

Is it true that TCP is short for TCP/IP and they mean the same thing? Is it possible for TCP to be built on top of another protocol besides IP?
101
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7answers
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IP address that is the equivalent of /dev/null

Is there an IP address that would result in any packet sent to be ignored (blackholed)? I know I can always set up a router with an IP address and then just have it ignore all packets sent to it, but ...
92
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10answers
31k views

Are IP addresses with and without leading zeroes the same?

I have a security system and the network setting only allows a three-digit IP address. I can't set it to 192.168.2.100, instead I have to use 192.168.002.100. Are these two IP addresses different? Do ...
89
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6answers
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Why is localhost IP 127.0.0.1?

I wondered what is the origin of the decision to make localhost's IP address 127.0.0.1. What is the "meaning" of 127? what is the "meaning" of 0.0.1?
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2answers
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Why does Qatar use a single IP address when 800,000 IP addresses are allocated to it?

In discussions about IP address banning, IP 82.148.97.69 is often cited as an example. According to Wikipedia, this IP address is the public address of "the entire nation of Qatar". There are two ...
83
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9answers
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Can you grab any IP address on the Internet?

On a personal network (LAN) one can simply grab an IP address. If you choose the same IP address as an existing client, you get problems. There are companies like IANA and ICANN that are in charge of ...
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7answers
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Do servers hold one website only?

As from what I understand the DNS link the domain name with the IP address of the server the website is stored on, does that mean each server can only hold one website? If they don't, how does calling ...
74
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15answers
279k views

Windows command that returns external IP

Is there a command by which I can find my external IP of my router or my NAT\DSL Router, etc., eliminating the need to visit whatsmyip.net or similar.
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4answers
9k views

How do web servers know whether you're using direct IP address access?

Some web servers, when accessed using their IP address, return an error that direct IP address access is not allowed. I've been wondering for some time how this works. I mean, doesn't the browser ...
59
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8answers
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Do two computers connected on the same Wi-Fi have the same IP address?

Do two computers connected on the same Wi-Fi have the same IP address (for example, my dad's computer and my computer, at home)? If so, how does the outside world distinguishes one computer with the ...
53
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7answers
110k views

How can I own an IP address?

How can I own an IP address like I do with domains? I have done some research and it seems that you can't buy a single IP, but rather you have to purchase a range of IP addresses. Update : Important ...
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9answers
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Why are subnet-masks relevant for the individual computer on the network?

I understand how subnet-masks are used to divide a network into sub-networks, but, why does every computer in the network need to know the subnet-mask and not just the router? I could understand it, ...
49
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7answers
128k views

Is it possible for many domain names to share one IP address?

Is it possible for many domain names to share one IP address? For example, www.xjtl.com, www.fmie.com, sdmfl.com, etc. Hundreds of domain names share just one IP – when you do a DNS query for each of ...
41
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9answers
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Why do we need subnet mask?

Since a IPv4 address already gives the information of the network and and host, why do we still need a subnet mask? The 1st Octet already specify the network class (1-127: A, 128-191: B, 192-223: C ...
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3answers
23k views

How does my router resolve a URL like http://router.asus.com/ to its IP address?

Typically I connect to my router by its IP address of 192.168.1.1. However, I am also able to connect to it at the URL router.asus.com. My computer does not have a connection to the Internet. How ...
39
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12answers
743k views

Windows command to display all IP addresses

I know there is a single line of a command and its arguments that can help display all computer IP addresses (those that are being used) on a LAN, and my computer is also a client, as one of those ...
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9answers
75k views

How can I get my public IP address from the command line, if I am behind a router?

Is there a way for me to get my public (WAN) IP address on the command line? I am behind a router (LAN network), with a dynamic IP address assigned by my ISP. I have seen solutions using an external ...
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5answers
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What keeps you from changing your public IP address and wreaking havok?

An interesting question was asked of me and I did not know what to answer. So I'll ask here. Let's say I subscribed to an ISP and I'm using cable internet access. The ISP gives me a public IP address ...
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5answers
9k views

How can every single device on a network have a different public IP?

I'm at a computer camp, and I noticed that every single device connected to the network has a different public IP, which really surprised me. What is even more strange is that their public IPs are ...
36
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10answers
306k views

How to find the IP Address of a vm running on VMware (or other methods of using VM)

I am running VMware Workstation on a Linux box. When I power on a centOS (Linux) virtual machine I cannot get mouse or keyboard control of the machine. I suspect that it has something to do with ...
36
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9answers
188k views

Find an unknown static IP + subnet mask of device?

I have a device set with a static IP and subnet mask. I do not know the IP or subnet mask. How can I find the devices IP and subnet mask? It is a piece of hardware, not a PC. It will not take an IP ...
35
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2answers
116k views

How to route only specific subnet (source ip) to a particular interface?

How to route only specific subnet (source ip) to a particular interface? OS: Linux I know I can do easily by destination IP by using something like route add 1.2.3.4/24 dev eth4 but I do not ...
35
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2answers
66k views

How does bridged networking work in Virtualbox?

How does bridged networking work? I have looked through the VirtualBox manuals but nothing extremely technical came up (It was just a generic gloss over of the topic). How does it assign a ...
34
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4answers
178k views

How to find my DNS Server address in Windows 7

What is the easiest way to know my current DNS server's IP address or domain name? I am trying to troubleshoot my broadband Internet connection under Windows 7.
33
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4answers
6k views

IP address: 000 simplifies to 0?

I was setting up my Ubuntu with brother printer driver and was trying to use my printer's IP to connect my pc to the printer. On my printer, the IP address is 192.168.000.008. So I entered this in my ...
32
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3answers
9k views

Why does the registered domain name “localtest.me” resolve to 127.0.0.1?

I was reading an article about Server-Side Request Forgery. In that article the attacker found that 127.0.0.1 was open to the internet. The victim then blocked 127.0.0.1, but because many other IPs ...
31
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4answers
17k views

Services that just return your public IP as text [closed]

I'm writing a script that does dynamic DNS updates for me, but my server is behind a router, and so I need to use a web service to determine my public IP. So far I've found this one which returns ...
30
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3answers
8k views

Why can I ping 10.0.0.0/8 addresses from a 192.168.1.0/24 subnet?

My home network uses a 192.168.1.0/24 subnet, and when I ping 192.168.1.137 I get a response saying the host is unavailable (as expected because I don't have any machines using that address) However, ...
29
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5answers
38k views

How do IP answer packets reach their destination inside of a private LAN? [duplicate]

This is a little theory question that has been confusing me for a pretty long time. Basically, if we are inside of a private LAN, and we want incoming packets to reach, for example, an HTTP server ...
27
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3answers
6k views

Why does searching “0.693” bring me to “0.0.2.181”? [duplicate]

While working on math, I encountered a number and wondered if it had any significance. So, in the browser search bar I entered it ("0.693"). I got redirected to the IP address 0.0.2.181, which ...
27
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4answers
12k views

Are subnets always contiguous 1s? [duplicate]

I understand the basic premise behind subnet masks, such as 255.255.255.0. But all the subnet examples I’ve seen have been (from left-to-right) contiguous 1s (HI bits). For instance, 255.255.0.0 (/16) ...
25
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5answers
25k views

Ethernet vs TCP vs IP?

What is the difference between Ethernet, TCP, and IP in simple (simple abstract) terms? Please do not copy from Wikipedia...
25
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3answers
62k views

On Windows, how to determine route for IP destination?

How can I determine the IP route taken for a specific IP destination (without looking at "route print" and figuring it out manually)? In OS X there's route get 1.2.34 and in Linux there's /sbin/ip ...
25
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2answers
68k views

How do I setup a virtualbox server with a static ip?

I'm trying to get a Virtualbox instance running with a very specific networking setup. Here's what I have right now: I have a laptop running Ubuntu, hosting a Debian Virtualbox. My loptop regularly ...
24
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2answers
24k views

Does the order of entries in the routing table matter?

Does the routing order matter: > route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 123.x.x.151 0.0.0.0 255.255.255.255 UH ...
24
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9answers
54k views

Is it possible to host a web server from behind a NAT

My PC is behind a NAT router that has a public IP address. If I want to host a website then I believe I need a domain name which I can purchase from some site which would pledge to resolve all DNS ...
23
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5answers
171k views

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 ...
23
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7answers
24k views

Why can a network address not be a valid host address?

So... I have studied for CCNA and such and been working with IP networking at the least the past 8 years or so. I have always seen and been told that the network address for a subnet is not a valid ...
22
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5answers
6k views

Is it possible to use global IP addresses without internet?

Is it possible to use global IP addresses without internet? Obviously, private IP addresses should be used without internet access. But I'm curious whether we can use any IP address as private IP. Is ...
22
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2answers
45k views

What is the difference between a subnet mask and a netmask?

Is there any logic in using two different names for determining host ID and net ID? For example, if you type print route in a Command Prompt you get things with netmask, but the IPv4 settings seems ...
22
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4answers
87k views

Possible to “ping” url:port? (OS X-GeekTool)

I'm trying to use GeekTool (Mac pref pane... basically just embeds output of a shell command/script on the desktop... http://lifehacker.com/#!244026/geek-to-live--monitor-your-mac-and-more-with-...
22
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6answers
86k views

How to make my IP publicly accessible to make my local Tomcat server public?

I'm working on my desktop computer. On this machine I also run Tomcat for my Java development so that I can visit my local address: http://192.168.1.1:8080/myapp Now I go to whatsmyip.com and get ...
21
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5answers
155k views

How can I connect via SSH (Putty) to my VMWare machine (Ubuntu)?

I'm trying to connect to my VMWare (Workstation 7.1.3) machine (Ubuntu Lucid) via SSH. I've read through some other posts, but I can't figure this out. I ran ifconfig, and got a inet addr: and Bcast ...
21
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3answers
53k views

How to map an IP adress to localhost?

I want to map the IP address 192.168.1.222 to 127.0.0.1 so that if I use 192.168.1.222 in the web browser or ping command I get the response (and that from my 127.0.0.1). Is this possible via ...
21
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2answers
7k views

ip versus ifconfig

After reading this answer, I began my quest for the difference between ip and ifconfig for *nix systems. I soon learned that ip had "more" features than ifconfig, but what's the real difference? Is ...

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