Networks - EdexcelIP addressing

At the internet layer, the IP - Internet Protocol - part of the TCP/IP protocol stack needs each node to have an IP address assigned to it. This address consists of four sets of up to three digits, each with a maximum value of 255. Each set is separated by dots. An example is:

192.168.0.254

When a node wants to send a message to another node, it uses the recipient node's IP address as the destination.

The method of addressing using four sets of digits held in 32 bits is called IPv4. When IPv4 was devised, the range of addresses it allowed was deemed to be sufficient. However, the huge increase in internet-enabled devices led to IPv4 running out of addresses. A new version - IPv6 - has been introduced, significantly increasing the number of possible addresses to trillions. IPv6 addresses are held in 128 bits.

Transmissions over a network can be extremely large. To send a large message in one go can be impractical, as both the sending and receiving node are tied up with one communication.