NOTE: 127.x.x.x is reserved for loopback testing on the local system and is not used on live systems.

Every IP address can be broken down into 2 parts, the Network ID(netid) and the Host ID(hostid).

All hosts on the same network must have the same netid. Each of these hosts must have a hostid that is unique in relation to the netid.

IP addresses are divided into 4 octets with each having a maximum value of 255. We view IPv4 addresses in decimal notation such as 124.35.62.181, but it is actually utilized as binary data.

The previous information on TCP/IP has referred to IPv4, however, this addressing scheme has run out of available IP addresses due to the large influx of internet users and expanding networks.

As a result, the powers that be had to create a new addressing scheme to deal with this situation and developed IPv6. This new addressing scheme utilizes a 128 bit address (instead of 32) and utilizes a hex numbering method in order to avoid long addresses such as 132.64.34.26.64.156.143.57.1.3.7.44.122.111.201.5. The hex address format will appear in the form of 3FFE:B00:800:2::C for example.

Also known as hardware address or ethernet address, A MAC address is a unique code assigned to most networking hardware.

MAC Addresses are in a 48-bit hexidecimal format such as 00:2f:21:c1:11:0a.

They are used to uniquely identify a device on a network, and for other functions such as for being authenticated by a DHCP server.