Routing - Basics - Hirschmann Power MICE User Manual

Routing - Basics

2 Routing - Basics
A router is a node for exchanging data on the layer 3 of the ISO/OSI layer
model.
This ISO/OSI reference model had the following goals:
To define a standard for information exchange between open systems;
To provide a common basis for developing additional standards for open
systems;
To provide international teams of experts with functional framework as the
basis for independent development of every layer of the model;
To include in the model developing or already existing protocols for
communications between heterogeneous systems;
To leave sufficient room and flexibility for the inclusion of future
developments.
The reference model consists of 7 layers, ranging from the application layer
to the physical layer.
7 Application
6 Presentation
5 Session
4 Transport
3 Network
2 Data-Link
1 Physical
Table 1: OSI reference model
Routing L3E
Release 4.2 08/08
Access to communication services from an
application program
Definition of the syntax for data communication
Set up and breakdown of connections by
synchronization and organization of the dialog
Specification of the terminal connection, with the
necessary transport quality
Transparent data exchange between two transport
entities
Access to physical media and detection and
resolution of transmission errors
Transmission of bit strings via physical media
11