Explain the concepts and capabilities of IP Datagram.Data transmitted over an internet using IP is carried in messages called IP datagrams.
Like all network protocol messages, IP uses a specific format for its datagrams.
The IPv4 consists of the following fields:
1. Version: the version of IP used to generate the datagram. For IPv4, this is of course the number 4
2. Internet Header Length: Specifies the length of the IP header, in 32-bit words.
3. Type of service: information to provide quality of service features
4. Total Length
5. Identification: it can be used if the datagram must be fragmented by a router during delivery and then for reassembling.
6. Flags: (Don’t Fragment, More Fragment)
7. Fragment Offset: When fragmentation of a message occurs, this field specifies the offset, or position.
8. Time to Live: specifies how long the datagram is allowed to “live”
9. Protocol: ICMP, TCP, UDP, etc
10. Header Checksum: to provide basic protection against corruption in transmission.
11. Source Address
12. Destination Address
14. Padding: if number of bits used for options is not a multiple of 32, then padding is added