360 Systems DigiCart/EX - Manual (Page 94)

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• Networking
Choosing a Server
The Ethernet Audio system is designed to work with standard computer hardware, Windows
operating systems, and storage systems. While we use the term server, it is acceptable to use a
suitably appointed standard PC.
One of the first choices to be made is to specify the size of the hard drive system, based on how
much audio material will be stored. Below is a table showing the approximate number of hours of
audio per decimal Gigabyte for various formats:
Sample Rate Word Size Hours/GiB
44.1KHz 16 bit 211
48Khz 16 bit 194
48KHz 24 bit 129
Storage Time Per Gigabyte for Various Formats
While it is possible to use network attached storage or drive letter-mapped network storage locations
to offload stored audio, it is not possible to use these for DigiCart/EX Network Drives because the
NFS service will only share local devices.
∗
The next consideration is whether the system is intended to support direct recording and playback
for a large number of DigiCart/EXs, or if the primary use is for file backup and sharing with minimal
direct recording and playback.
Systems that are only used for file transfer are not relying on the server and network for mission
critical playout. File transfer operations will proceed with whatever bandwidth is available, but
playout and record require a minimum of bandwidth and a maximum of response time.
Systems that are only used for file transfer can theoretically support more than 16 DigiCartEXs,
assuming DHCP is used to assign IP Addresses.
Systems that will play and record directly on the server may require a RAID 5 or 6 disk system to
guarantee high data throughput and reliability.
Tests using a recent model desktop computer with a SATA hard drive and Gigabit Ethernet interface
prove that it is possible to simultaneously run 16 DigiCartEXs in record and playback at 48KHz 24
bit. However, we recommend the use of a RAID array due to the higher reliability factor.
The system may require multiple Ethernet interfaces. Each network interface can handle 16
DigiCart/EX units. If the server needs to be connected to a local or wide area network this should be
through an additional separate interface. Contact 360 Systems Customer Support if you need further
guidance on specifying or configuring a large system.
Other system design criteria include redundant power and cooling, and the need for audio
monitoring from the server itself (many enterprise server systems do not include audio hardware on
the motherboard).
∗ It is possible to set up two servers, each with its own NFS service. When the DigiCart/EX detects more than
one NFS service on the network, it asks the operator to choose between two or more IP addresses before
presenting the available Net Drives. All Net Drives on a DigiCart/EX must be from the same NFS Service.