15Aug Understanding Internet Protocol

The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched internetwork using the Internet Protocol Suite. In the network model, this network is switched in the Internet layer. It does the work of delivering datagrams (packets) from the source host to the destination host uniquely based on its address. For this purpose the Internet Protocol initiates addressing methods and structures for packet encapsulation. Because of the abstraction provided by encapsulation, Internet Protocol can be used over different sorts of networks. This means, any network connecting two computers can be mix of Ethernet, FDDI, ATM, Wi-Fi, token ring, etc. This makes no difference to the higher layer protocols present in the network model.

The first major version of addressing mechanism, now referred to as Internet Protocol Version 4 (IPv4) is still the leading protocol of the Internet, even though the successor, Internet Protocol Version 6 (IPv6) is actively distributed throughout the world. IPv4, provides reliability on integrity of the packet, ensuring the IP header of the packet is free from error through the use of a checksum. This has a great disadvantage of discarding packets with bad headers on the spot, and with no required notification to either end. IPv6, on the other hand, has stopped the use of IP header checksums for the benefit of fast delivering of packet through routing elements in the network.