Tcp Ip Protocol Questions
IP packet fragmentation is a process in the TCP/IP Protocol where large IP packets are divided into smaller fragments to be transmitted over a network that has a smaller Maximum Transmission Unit (MTU) size. This fragmentation process ensures that the IP packets can be successfully transmitted and reassembled at the destination.
The process of IP packet fragmentation involves the following steps:
1. The sending host or router checks the size of the IP packet and compares it with the MTU size of the network it is about to transmit the packet on.
2. If the IP packet size exceeds the MTU size, the sending host or router divides the packet into smaller fragments. Each fragment contains a portion of the original IP packet's data.
3. The original IP packet's header is copied into each fragment, ensuring that the necessary information such as source and destination IP addresses, protocol information, and identification number is preserved.
4. The offset field in the IP header is set to indicate the position of each fragment within the original IP packet.
5. The sending host or router assigns a new identification number to each fragment to differentiate them from other IP packets.
6. Each fragment is then individually encapsulated into separate IP packets and transmitted over the network.
7. At the receiving end, the destination host or router collects all the fragments based on their identification numbers and offset values.
8. The fragments are then reassembled in the correct order using the offset values and the original IP packet's length field.
9. Once all the fragments are successfully reassembled, the original IP packet is reconstructed and delivered to the appropriate upper-layer protocol for further processing.
It is important to note that IP packet fragmentation should be minimized as it can introduce additional overhead and increase the chances of packet loss or retransmission.