It is much the same as a real-life package, in each packet it includes a source and destination, along with the content (or data) that is being transferred.
When the packets reach their destination or target, they reassemble together to become a single file or another contiguous block of data.
While the exact structure of a packet varies greatly between protocols, a typical packet includes two sections – a header and a payload.
The information store about Packet is in the header. For example, an IPv6 header includes the fields below:
1. Source address (128 bits) – This is IPv6 address of packet origin
2. Destination address (128 bits) – This IPv6 address is the packet destination key
3. Version (4 bits) – “6” for IPv6
4. Traffic class (8 bits) – It is used to make priority setting of the packet.
5. Flow label (20 bits) – This is a type of optional ID that labels the packet as
a specific flow on a part ; At the same time, it is used to separate multiple transmissions from a single origin.
6. Payload length (16 bits) – This is the size of data, which is defined in octets.
7. Next header (8 bits) – ID is the header that follows the current packet; It can also be TCP, UDP, or any other protocol.
8. Hop limit (8 bits) – This includes the maximum number of network hops (between routers, switches, etc.) before the packet drops; It is also called “TTL” in IPv4 .
The payload section of a packer includes the actual data that is to be transferred. This is actually a small part of a file, webpage, or other transmission, since individual packets are much smaller.
For example, the maximum size of an IP Packer Payload is around 65,535 bytes, or 64 kilobytes. The maximum size of an Ethernet packet or “frame” is only 1,500 bytes or 1.5 kilobytes.
Packets are always directed to transfer data correctly so that they can transfer data reliably and efficiently.
All data can be sent successfully by sending data in the form of small packets in place of a large file or a single block of data. In such a situation,
if no packet is received or “ dropped ”, then in that case only that dropped packet needs to be resent.
Whereas if a data transfer is encountered due to network congestion due to multiple simultaneous transfers, then the outstanding packets are reroute through a less congested path.