Table of Contents
The basis for the communication in a network is a way to uniquely identify different devices. For exactly that purpose the “Internet Protocol” (short IP) has been developed.
An IP-Address is a unique number, which identifies a device inside the currently used network. This number can be something like:
IPv4: 192.168.0.10
IPv6: fe80::884:34ae:8eaf:a586
The detailed difference between IPv4 and IPv6 can be looked up in the linked posts.
But let’s keep it simple.
An IP-Adresse can be seen as a “postal address” of your house to differentiate your house from your neighbours house. The only difference is that its not “Mainstreet 3, 8430 Leibnitz”, instead its “192.168.0.2” and that its not about houses, its about IT devices.
Why did we have to develop IPv6?
Basically IPv4 allows a maximum of 4.294.967.296 (232) devices, which in the grand scheme of the planet earth and its currently 7.7 billion people is not quite sufficient.
Therefore IPv6 was developed and allows a maximum of 340.282.366.920.938.463.463.374.607.431.768.211.456 (2128) devices which should suffice for quite some time.
Why was the internet protocol developed anyway?
Before the internet protocol it was not possible to connect 2 different network systems or let 2 computers from 2 difference network systems communicate with each other.
With the internet protocol it should be as easy as possible to connect multiple computers and networks with each outer without having to adjust things like baud rates or the need to “hardcode” specific address codes.
Main tasks of the internet protocol
- Address allocation
- Commands to build and breakdown connections
- Control of data flow via start und stopp commands
- Error detection via checksums, time-outs etc.
- Automatic error correction when an error has been detected
Main traits of the internet protocol
- Its independent on the architecture
- Connection to and from all network clients possible
- dynamic routing
The main tasks of the internet protocol have been split up into single “layers” – which build the Open Systems Interconnection model, in short OSI.
OSI-Layer Model
| Layer | Name | Protocol | Task/Description |
| 7 | Application | HTTP, FTP, DNS | Interaction with application |
| 6 | Presentation | SSL, TLS, MPEG | Convert- and Compression procedure |
| 5 | Session | NetBIOS, SMB | Management of Sessions |
| 4 | Transport | TCP, UDP | Connection Management |
| 3 | Network | IP, ARP, IPSec | Routing and Addressing |
| 2 | Data-Link | MAC, QoS, VLAN | Data Flow, Error Detection and Access Management |
| 1 | Physical | Ethernet | Coper- or Fibercable, WLAN, UMTS |