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Public DNS Servers

Domain Name Service (or Server or System) is an internet service that translate easily memorized domain names into IP numbers and vice-versa. DNS Servers can be better understands as Yellow page directory to the Internet. Every ISP runs DNS services for their customers and users. A user can also runs DNS service for its own. There are many DNS servers which are open for all, commonly known as Public DNS Servers. IP addresses of main Public DNS Servers are :- Google Public DNS Servers 1.   8.8.8.8 2.   8.8.4.4 3.   2001:4860:4860::8888 4.   2001:4860:4860::8844 Level 3 Public DNS Servers 5.     4.2.2.1 6.     4.2.2.2 7.     4.2.2.3 8.     4.2.2.4 9.     4.2.2.5 10.   4.2.2.6 OpenDNS Public DNS Servers 11.     208.67.222.222 12.      208.67.222.222 13.      2620:0:ccc::2 14.      2620:0:ccd::2 Norton Public DNS Servers 15.   198.153.192.1 16.   198.153.194.1 Comodo Secure Public DNS Server 17.   8.26.56.26 18.   8.20.247.20 Other Public DNS Server 19.

Why we have IPv6 after IPv4..... Where is IPv5 ?

IP or Internet Protocol, is the primary network protocol used on the Internet, introduced by Vint Cerf and Bob Kahn in 1974. IP version 0 to 3 was introduced and used between 1974 and 1979. After changes and refinements in initial IP protocol, version 4 was introduced in 1981, commonly known as IPv4, described in RFC 791 , which become the backbone of Whole Internet in no time. (IPv4 is know as v4 because it is the fourth version of IP not because it has 4 octets, which is a common myth). TCP/IP Protocol was designed as a part of project ARPANET, whose aim was to interconnect various universities and research institutes of USA. But with the dot com boom, TCP/IP grows like anything and its become a victim of its own success. In Early 90's, expert realized that we will exhaust the whole IPv4 number very soon and there is a need for a new protocol, which should be enough in size to serve the internet community for at least 30-40 years. This lead to new version of Internet Protoco

IPv6 Address Allocation BCP

Best Current Practices in for IPv6 Address Allocation This Best Practices document aims to provide IPv6 Address allocation guidelines that a network operator can follow while planning the IPv6  sub-netting  for its network (based on the issues faced and learning’s from IPv6 implementation in NKN and NIC network). Best Current Practice: 1. Sub-netting         IPv6 addresses generally written in Hex format. Each Hex number represents 4 bit, commonly known as nibble. A nibble boundary is a network mask that aligns on a 4-bit boundary. Sub-netting the v6 address at nibble boundary improves efficiency and make it easier to understand for humans* (Machine will anyway read it binary format  J ). Example of Nibble and non-Nibble Boundaries Sub-netting From the above example, we can clearly see that Sub-netting at the Nibble boundaries is easier to manage and do the sub-netting. * Condition may arise where you may have to