Some Special IP Addresses

IP Addresses

Short for Internet Protocol address, an IP or IP address is a number (example shown right) used to indicate the location of a computer or other device on a network using TCP/IP. These addresses are similar to those of your house; they allow data to reach the appropriate destination on a network and the Internet.

IPv4 vs. IPv6

As the Internet and technology evolve, there has been an increasing demand for IP addresses. To help meet the demand for IP addresses, there are two types of addresses used today, IPv4 and IPv6. Although you may only deal with an IPv4 address in your local home, school, or small office you should also be aware of IPv6 addresses for when you encounter them.

Below are Some Special IP Addresses

• 127.0.0.1
  Native address, mainly used for testing. On Windows systems, this address has an alias “Localhost”. Addressing such an address, it is not sent to the network interface. Unless an error occurs, a packet with the destination address “127.0.0.1” should never appear on the transmission medium.
• 0.0.0.0
  Strictly speaking, 0.0.0.0 is not a true sense of the IP address. It represents such a set: all unknown hosts and destination networks. “Unclear” here means that there is no specific entry in the local routing table to indicate how to reach it. On the machine, it is a “shelter”, all do not know the “three no” personnel, all sent to. If you set the default gateway in the network settings, the Windows system will automatically generate a destination address of 0.0.0.0 for the default route.
• 255.255.255.255
  Restrict broadcast addresses. For this machine, this address refers to all hosts on the network segment (the same broadcast domain). If translated into human language, it should be this: “Everyone in this room pay attention!” This address can not be router forwarding.
• 169.254.x.x
  If your host uses DHCP to automatically obtain an IP address, Wingdows will assign you an address if your DHCP server fails or if the response time is too long to exceed a system-specified time. If you find your host IP address is such a type of address, unfortunately, in all likelihood is your network can not function properly.

• 224.0.0.1
  Multicast address, pay attention to it and broadcast the difference. From 224.0.0.0 to 239.255.255.255 are such addresses. 224.0.0.1 refers specifically to all hosts, 224.0.0.2 refers specifically to all routers. Such addresses are used for some specific programs and multimedia programs. If your host is enabled IRDP (Internet Routing Discovery Protocol, the use of multicast function), then your host routing table should have such a route.
• 10.x.x.x、172.16.x.x -> 172.31.x.x、192.168.x.x
  Private addresses, which are heavily used in the enterprise internal network. Some broadband routers, also often use 192.168.1.1 as the default address. Private networks are not interconnected with the outside world, so it is possible to use arbitrary IP addresses. Such an address is reserved for use in order to avoid confusion in the future when it is connected to the public network. Private Networks with Private Addresses When connecting to the Internet, address translation (NAT) is used to translate private addresses to common legal addresses. On the Internet, such addresses can not appear.