Table of Contents
Centauri user manual revision level 01 /2007
61
7
Internet Protocol
So that this handbook is not more extensive than absolutely necessary, we assume
basic knowledge about the Internet Protocol (IP). If you are not familiar with the topic
“Internet Protocol”, we recommend you refer to the appropriate literature on the subject.
Every Merk II has a network interface card with a 10Base-T/100Base- TX-RJ-45
connection. The connection configures itself to the existing network speed (10 or 100
MBit/sec).
The Merk II supports the Internet Protocol, either connection-orientated (TCP) or without
connection (UDP) as a protocol on the network.
You can find more detailed descriptions of the various protocols in the
“
Glossary
”
.
All device types from the MERK II family can be remote controlled via the network
interface.
The devices of the CENTAURI 3000 series also permit the transport of digital audio
signals via the network interface.
Each Merk II can be connected to a normal local Ethernet via the network interface. Apart
from the physical connection it is only necessary to enter the unique IP address.
7.1.
Remote Control via IP
For management and control functions the Merk II provides two different protocols:
–
In the simplest case a TCP/IP connection is set up with a PC on which the remote
control software provided runs. The data exchange is achieved via a simple IP Port
Protocol. This protocol can also be used for the development of more complex control
systems.
–
For the integration into network structures, Merk II can be connected by means of a
management interface via the SNMP(v1) (Simple Network Management Protocol). For
this the gateway acts as 'Agent', i.e. a manageable device in the network. Information
about the current status of the device and the individual interfaces can be requested
via SNMP. The gateway can also trigger a network report (Trap) when a particular,
predefined event occurs that can be received and evaluated by the management
system.
7.2.
Digital Audio via IP
Besides the monitoring and management functions, the Merk II also provides the
possibility of audio transport via IP.
This means, for example, that a signal lying at the audio input can be transmitted into the
network using an TCP or UDP.
In the average case of audio data transport via IP, one IP-packet carries exactly one audio
frame. Depending on frame length and packet size there is a specific overhead in each IP-
packet. An exception can occur if the data transport isn’t working correctly due to different
possible reasons, e.g. network problems. In this situation, if the IP-packets are refused
and have to be sent again, the audio frames are allocated to the IP packets in a different
way.
