What is a Network or IP Address

An Internet Protocol address (IP address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication.^[1][2] An IP address serves two principal functions: host or network interface identification and location addressing.

Internet Protocol version 4 (IPv4) defines an IP address as a 32-bit number.^[2] However, because of the growth of the Internet and the depletion of available IPv4 addresses, a new version of IP (IPv6), using 128 bits for the IP address, was developed in 1995,^[3] and standardized in December 1998.^[4] In July 2017, a final definition of the protocol was published.^[5] IPv6 deploymenthas been ongoing since the mid-2000s.

IP addresses are usually written and displayed in human-readable notations, such as 172.16.254.1 in IPv4, and 2001:db8:0:1234:0:567:8:1 in IPv6. The size of the routing prefix of the address is designated in CIDR notation by suffixing the address with the number of significant bits, e.g., 192.168.1.15/24, which is equivalent to the historically used subnet mask255.255.255.0.

The IP address space is managed globally by the Internet Assigned Numbers Authority (IANA), and by five regional Internet registries (RIRs) responsible in their designated territories for assignment to end users and local Internet registries, such as Internet service providers. IPv4 addresses have been distributed by IANA to the RIRs in blocks of approximately 16.8 million addresses each. Each ISP or private network administrator assigns an IP address to each device connected to its network. Such assignments may be on a static (fixed or permanent) ordynamic basis, depending on its software and practices.

IP address classes

With an IPv4 IP address, there are five classes of available IP ranges: Class A, Class B, Class C, Class D and Class E, while only A, B, and C are commonly used. Each class allows for a range of valid IP addresses, shown in the following table.

Class	Address range	Supports
Class A	1.0.0.1 to 126.255.255.254	Supports 16 million hosts on each of 127 networks.
Class B	128.1.0.1 to 191.255.255.254	Supports 65,000 hosts on each of 16,000 networks.
Class C	192.0.1.1 to 223.255.254.254	Supports 254 hosts on each of 2 million networks.
Class D	224.0.0.0 to 239.255.255.255	Reserved for multicast groups.
Class E	240.0.0.0 to 254.255.255.254	Reserved for future use, or research and development purposes.

                                                                STEPS

WINDOWS

To find the IP Address on a PC:

On a College computer:

• In the System Tray (next to the clock), you should see a white triangle pointing upwards. Click it to reveal more icons. Find the one that looks like a computer with an "i" over it (BGInfo) and click it. Look for the IP: line.

On a personal computer, or if that does not work:

1. Click the Start menu button on the Windows taskbar.
   • If you are using Windows XP, click 'Run...'
2. Type 'cmd' in the text box that appears and then press Enter. A black "command prompt" window launches on the desktop.
3. In this command window, type ipconfig and hit Enter.
4. Look next to “IPv4 Address” for the IP Address. (There may be more than one, if so, note which heading they appear under.)

To find the MAC/Physical Address/Ethernet ID on a PC:

1. Click the Start menu button on the Windows taskbar.
2. Type 'cmd' in the text box that appears and then press Enter. A black "command prompt" window launches on the desktop.
3. In this command window, type ipconfig /all and press Enter.
4. Look for Physical Address.
   • The one listed under Ethernet adaptor Local Area Connection is for your wired connection.
   • The one listed under Wireless LAN adapter Wireless Network Connection is for your wireless connection.