Wheatstone Corporation WheatNet-IP BLADE3, Техническое руководство, Страница: 102 / 366

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WheatNet-IP BLADE 3 / Jan 2016
E T H E R N E T N E T W O R K S A N D S W I T C H E S
Ethernet Networks and Switches
Overview
The underlying network plays a major role in the successful deployment of your
WheatNet‑IP system. In the IP audio world, the Ethernet network is the analog of the
punch block wall in a traditional broadcast plant. As such, careful consideration should
be given to network topology when planning the installation. Because the size and type
of network you design and deploy directly depends on the amount of WheatNet‑IP and
surface hardware you are installing, it is wise to build a network that has reasonable
overhead and room to grow as formats and audio distribution needs change over time.
Gigabit Ethernet Technology
The WheatNet‑IP system uses 1000BASE‑T gigabit Ethernet technology exclusively
to transport audio and control packets between BLADE 3s. Because the WheatNet‑IP
system uses gigabit connectivity, the possibility of link overload is drastically reduced
when compared to competing 100BASE‑TX systems. Each Gigabit connection is
capable of handling literally hundreds of audio streams, along with associated GPIO,
system configuration, and network monitoring capabilities. Advantageously, the cost of
gigabit technology is rapidly decreasing due to economy of scale benefits gained by cross
application use of the technology.
Choosing Ethernet Switches
There are literally hundreds of choices of Ethernet switches on the market today. Chances
are you have a compatible switch in your facility already. However it is recommended that
the WheatNet‑IP network be isolated from any existing network using separate switches
or a unique VLAN on existing switches.
Switch Feature Considerations
• 10/100/1000 Ports – When looking at switches, make sure all the ports support
full‑duplex 1000BASE‑T connections. Some switch models are touted as Gigabit,
but really only have one or two 1000BASE‑T ports.
• Hubs – Packets entering a hub or repeater are broadcast out of every other port
on the device. Gigabit hubs must be avoided because they are a single collision
domain and can slow your GbE audio network to a crawl. If you find a really good
deal on a Gigabit “switch” be sure it is not really a hub.
• Throughput – Is an important specification when deciding on a Gigabit switch.
Throughput is the amount of cumulative data traffic a switch is capable of
transceiving. Ideally an eight port 1000BASE‑T switch should incorporate an
8Gbps non‑blocking switch fabric. Low throughput switches typically use input
buffering techniques susceptible to Head‑Of‑Line blocking which can adversely
affect the real time performance of medium to large IP audio networks.
• Rack Mounting – Rack mounting is a useful option for most broadcast systems.
• Chassis Based – Large enterprise systems may benefit from installing or expanding
existing chassis based managed switch solutions.
WheatNet-IP BLADE 3 / Feb 2019