Introduction to IPv4 & IPv6
About Internet Protocol Version 4 (IPv4) –
Internet Protocol version 4 is fourth version of IP, It was the first version deployed for production in the ARPANET in 1983. It is widely used protocol in data communication over different kinds of networks.
IPv4 is a connectionless protocol used for packet-switched networks. It operates on a best effort delivery model, that does not guarantee delivery neither it assure proper sequencing or avoidance of duplicate delivery. These aspects include data integrity, which are address by an upper layer transport protocol, such as the Transmission Control Protocol (TCP).
Key Points –
– IPv4 uses 32-bit addresses, which limits the address space to 4294967296 addresses.
– IPv4 reserves special address blocks for private networks (~18 million addresses) and multicast addresses (~270 million addresses).
– It is written in the dot-decimal notation, which consists of four octets of the address expressed individually in decimal numbers and separated by periods.
IPv4 Private address Range –
Class full Description
Number of Addresses
Special IPv4 Address –
The Internet Engineering Task Force (IETF) and the Internet Assigned Numbers Authority (IANA) has restricted various IP addresses for general use and reserved it for special purposes. Some reserved IP addresses are used for maintenance of routing tables, multicast traffic, operation under failure modes, or to provide addressing space for public unrestricted are used only for private networks.
|100.64.0.0/10||Shared Address Space|
|192.0.0.0/24||IETF Protocol Assignments|
|126.96.36.199/24||IPv6 to IPv4 relay|
|188.8.131.52/4||IP multicast (former Class D network)|
|240.0.0.0/4||Reserved (former Class E network)|
About Internet Protocol Version 6 (IPv6) –
Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), IPv6 was developed by the Internet Engineering Task Force (IETF). The communications protocol provides an identification and location system for computers on networks and routes traffic across the Internet.
IPv6 uses 128-bit address theoretically, it allow 2 pow128 , or approximately 3.4×10 pow38 addresses. Every device on the Internet is allocated with a unique IP address for identification and location definition. IPv6 provides other technical benefits in addition to a larger addressing space.
IPv6 addresses are represented as eight groups of four hexadecimal digits, groups are further separated by colons.
for example 2001:0db8:0000:0042:0000:8a2e:0370:7334, but methods to abbreviate this full notation exist.
An IPv6 address may be abbreviated to shorter notations by application of the following rules –
1. One or more leading zeroes from any groups of hexadecimal digits are removed; this is usually done to either all or none of the leading zeroes.
For example, the group 0042 is converted to 42.
2. Consecutive sections of zeroes are replaced with a double colon (::).The double colon can be used once in an address, as multiple use would render the address indeterminate. RFC 5952 recommends that a double colon must not be used to denote an omitted single section of zeroes.
An example of application of these rules:
– Initial address: 2001:0db8:0000:0000:0000:ff00:0042:8329
– After removing all leading zeroes in each group: 2001:db8:0:0:0:ff00:42:8329
– After omitting consecutive sections of zeroes: 2001:db8::ff00:42:8329
– The loopback address, 0000:0000:0000:0000:0000:0000:0000:0001, may be abbreviated to ::1 by using both rules.