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498

Everybody is over-complicating it with RFCs, IP classes, and such. Simply run a few tests to see how the ping command parses the IP input by the user (extraneous chaff removed): > ping 1 Pinging 0.0.0.1 with 32 bytes of data: > ping 1.2 Pinging 1.0.0.2 with 32 bytes of data: > ping 1.2.3 Pinging 1.2.0.3 with 32 bytes of data: > ping 1.2.3.4 ...


136

There are two reasons for this: First, a '0' prefix indicates an octal number. Since oct(072) = dec(58), 192.168.072 = 192.168.58. Second, the second-to-last 0 can be dropped from IP addresses as a shorthand. 127.0.1 is interpreted as 127.0.0.1, and in your case 192.168.58 is interpreted as 192.168.0.58.


90

In addition to @neu242's important point about octal notation, and observation that IP addresses can be shortened, the other critical piece is knowing how shortened IP addresses are interpreted. One might naively guess that if some of the four numbers are missing, the parser would add zero-filled bytes onto the end (or the beginning) of the sequence of ...


63

There's specifically a blackhole prefix in IPV6, as described in RFC 6666, it's 100::/64. IP4 does not have an explicit black hole like that, but a non-existent host on one of the reserved blocks would have that effect. (e.g., 240.0.0.0/4 is "reserved for future use" and will not be routed by anything.)


53

I know who chose these address ranges. Unfortunately, he is dead, so I cannot ask him exactly why he chose them, but I can make some well informed guesses. There isn't much online dating prior to the mid-1990s, when the Internet really started to take off. What history of the Internet exists is mostly in the RFCs which define it, which date back to 1969, at ...


49

Type this into a .bat file. You can then create a shortcut to it and place it in the taskbar, start menu, or assign a hotkey. ipconfig | find "IPv4" | find /V "192.168." | CLIP What it does: First find returns all the lines that contain IPv4. If you have multiple network adapters, from example from VMWare, you may want to exclude them. That's where find ...


47

It's not MS it is the ISOC ;-) Have a look at reserved IP address RFC 5735 under special use IPv4: here 169.254.0.0/16 - This is the "link local" block. As described in [RFC3927], it is allocated for communication between hosts on a single link. Hosts obtain these addresses by auto-configuration, such as when a DHCP server cannot be ...


39

You are not pinging the same interface, without any physical interfaces you still have a "local host". Your localhost is used to refer to your computer from its "internal" IP, not from any "external" IPs of your computer. So, the ping packets don't pass through any physical network interface; only through a virtual loop back interface which directly sends ...


38

The use of 169.x.x.x addresses are defined within a standard colloquially known as APIPA - Automatic Private IP Addressing. In a nutshell, if a network device has not been assigned a fixed (static) address and cannot obtain one by asking (DHCP), the device says to itself, "Well, I'd better make up an address of my own so I can communicate on this network", ...


33

There is such a thing as network Black hole. If there are no devices in the network with IP address 192.168.0.10, then this IP address is kind of black hole and it will "discard" all the traffic to it, simply because it does not exist. Protocols which keep track of connection state (TCP) can detect a missing destination host. It will not happen with UDP ...


30

I'm a forensics major, and I'd say "no, not really". I'm assuming you're looking at the header and the information from there. Its painfully simple to run things through a proxy to hide your actual IP address. There's a few possible scenarios here - lets talk about the most obvious - he's using a proxy service, tunneling things through there and the ip ...


29

Because it made sense at the time? :-D Remember, back when the private IP address ranges were assigned, there were several issues network engineers had to contend with: Some of the most powerful routers at the time had about as much CPU power and RAM storage as today's pocket graphing calculators--and some of the ones today still run circles around ...


28

When using DHCP, the (Wi-Fi) router is the DHCP server, that is, the network host that assigns the IP addresses. The computers do not choose their address from the pool; the router chooses and tells the computer what its address will be. Therefore, you have two options if you want a computer to always have the same IP address: Option 1: IP address ...


26

You have to Google for "free http proxy", some of the lists you get as a result classify geographically the proxies, find one of those and then choose a US located proxy. Afterwards set your browser to use as HTTP proxy your selected proxy (what are the steps to do this depends on the browser you use). Some proxies work better than others and some just ...


25

You have to consider also that an ip can be represented by integers added together in significance to their position. 192.168.0.58 is : 192 * 256^3 + 168 * 256^2 + 0 * 256^1 + 58 * 256^0 Here's the cool thing: 192.168.58 will be 192.168.0.58 because 0 * 256^1 + 58 * 256^0 = 58 192.11010106 will also be 192.168.0.58 because 168 * 256^2 ...


23

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 would not be possible.


21

Create a shortcut to BGinfo (a program that shows system information on the Windows background). Double-click. : )


20

Yes: http://en.wikipedia.org/wiki/Loopback The most commonly used IP address on the loopback device is 127.0.0.1 for IPv4, although any address in the range 127.0.0.0 to 127.255.255.255 is mapped to it. or from the RFC itself: RFC 3330 - Special-Use IPv4 Addresses 127.0.0.0/8 - This block is assigned for use as the Internet host loopback ...


20

The loopback interface exists independently of your Ethernet interface(s). Even without the complication of IPv6 you'd have two distinct addresses. Loopback IPv4 address : 127.0.0.1 Your Ethernet interface's IPv4 address : 192.168.0.10 The loopback interface might well be in a different software layer, more remote from real hardware. I doubt it depends ...


19

In the primordial Internet, the network now denoted 10.0.0.0/8 was allocated to the ARPANET. By the time the IETF and IANA got around to assigning private address ranges, ARPANET was defunct, and its former address space was available for private use. The other two ranges made Class B and Class C networks available for private IPs, in addition to ...


17

The quickest way is to use Angry IP Scanner I use it for the same way you want to!


17

Nmap is available for Windows: # nmap -sP 10.0.10.1-100


17

The oldest and probably most reliable way to bind a dynamic (or any kind) of IP to a domain name is DynDNS. You have clients for almost any operating system, and once it's set up, it will run for years without you noticing anything.


17

I wonder what each interface is. lo0 = loopback gif0 = Software Network Interface stf0 = 6to4 tunnel interface en0 = Ethernet 0 fw0 = Firewire en1 = Ethernet 1 vmnet8 = Virtual Interface vmnet1 = Virtual Interface Something like that. Also, which of these is the IP interface ? There hasn't been "the" IP interface since many years ago. All of ...


16

In your PHP script, when you access it by IP address, you also need to send a Host: header in your request with the correct domain name. This question on Stack Overflow explains how to do it: http://stackoverflow.com/questions/356705/how-to-send-a-header-using-a-http-request-through-a-curl-call


16

Yes, you can (sometimes) resolve an IP Address back to a hostname. Within DNS, an IP Address can be stored against a PTR record. You can use nslookup to resolve both hostnames and IP addresses, though use of nslookup has been deprecated for quite some time. For best results, you should really get a hold of the dig tool. If you're a linux user, this is ...


15

try this: grep -E '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' /etc/hosts which matches all expressions from 0.0.0.0 to 999.999.999.999 with grep -Eo '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' /etc/hosts you will get IP addresses only note: on solaris probably egrep will do the job.


15

DHCP static leases are much better. They're easily managed, many consumer grade and SOHO routers have the ability to do so, and it enables everything to be done under one single management tool.


14

From MAC Address vs IP Address When the packet is being sent out to a statipn that is on the same network LAN segment, only the MAC address is needed. When the packet goes beyond, to different networks and travels through routers, the MAC address is still contained in the packet, but only the IP address is used by the routers. Also ...


14

All of these are private network IP adresses, the last one is typically used for home networks, but as it offers the smallest number of sub-adresses, the other ones might be preferred for larger networks like e.g. company intranet. IP address range number of addresses classful description 10.0.0.0 – 10.255.255.255 16,777,216 ...



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