Studer OnAir 3000, Operating Instructions Manual

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OnAir 3000 Digital Mixing Console
Networking 9-3
Date printed: 31.10.08 SW V3.0
9.2.6 OnAir 3000 Component Packet Types
OnAir 3000 components use
UDP broadcast or UDP multicast packets
(UDP:
User Datagram Protocol), and
TCP sessions.
Broadcast packets are used in
OnAir 3000 components for two different reasons:
• Detection of the OnAir 3000 network domain, i.e., searching all OnAir
3000 components on the network (this happens only on startup of an OnAir
3000 component)
• Periodical checks whether all other (or new) nodes are still alive.
One broadcast/multicast packet is less than 100 Bytes (UDP size on the net-
work) and only sent out every second.
Because of this fact the total amount of
broadcast traffic in a OnAir 3000 network domain is negligible.
The resulting
broadcast network load is very low – it would require more than 1000 OnAir
3000 components within one network in order to utilize 1% of the available
100 Mbit/s capacity.
TCP sessions are established during normal operation. This traffic is based
on unicast IP packets and allows a high degree of scalability.
9.2.7 Traffic Shaping
It is important that outside network traffic must not disturb the OnAir 3000
network domain.
The best approach to this is by using manageable switches
or routers to interconnect the IT infrastructure with the OnAir 3000 network
domain, and either to apply broadcast traffic limitations or to completely
eliminate broadcast packets between the two network domains. This will
also eliminate OnAir 3000 component broadcast packets to be sent to the
customer’s IT network.
Traffic shaping will guarantee the proper functioning of the OnAir 3000
system, even if a network error or a malware condition should occur within
the IT network.
9.2.8 IP Filtering
To make sure that no external IT network traffic will disturb the OnAir 3000
network domain, IP filters can be applied in the manageable switch in addition
to broadcast traffic shaping. This will completely block out any undesired and
unnecessary access to the OnAir 3000 network domain and its components.
If OnAir 3000 components such as the LogScreen are placed outside the
OnAir 3000 network domain, its fixed IP address can be set up as an “access
granted” (pass-thru) entry in the IP filter table on the manageable switch.
9.2.9 Mixed Mode
Theoretically the OnAir 3000 network domain and the IT network may be
identical (no traffic shaping, IP filtering or routing between the two networks)
which, usually, does not cause any problems for smaller and mid-sized sys-
tems
.