DEVOS -- Enterprise Video System
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DEVOS
Because of network protocol overhead and other factors, this theoretical usage
should be supported by a network capacity that is 20% to 50% higher. For example, to
support 5,000 live viewers the network should support 3 to 3.75 Gbps, plus network
capacity for users to perform other routine network actions. Also note that this
example uses a single stream at 500 Kbps. The number doubles if the stream is 1
Mbps, and consideration must be made for the total number of live streams available.
Experience shows that while there may be 5,000 possible viewers, the actual number
at any given instant is typically much smaller (because viewers tend to come-and-go,
and not all possible viewers actually participate). It is therefore possible to be
completely successful in a de-rated configuration. Live streaming capacity can be
greatly increased by placing Discover Video StreamPump
®
at strategic locations.
StreamPump will automatically receive the live stream and distribute it to viewers
within a network or sub-network, vastly reducing both the server's load and the
network utilization.
Viewing of Video-on-Demand is the same as live, except usage tends to be spread
out over time (there is no compelling reason to tune in "now"). Actual network usage
cannot be well predicted because it will be different for each use case, and network
professionals should monitor network usage and make adjustments as needed.
Generally, it is good practice to provide sufficient bandwidth capacity for the worse-
case usage, but experience is the best guide.
For very large live streaming events, DEVOS also supports IP multicast, allowing
an unlimited number of viewers to view live streams using the bandwidth of
only one.
Clustering
Clustering increases performance by allowing multiple servers to behave as one.
When you add an additional DEVOS server to your system, the content is
automatically duplicated on all servers in your cluster and requests for viewing are
automatically spread out via "round robin" load balancing. Thus, if the capacity of
one server is 4 Gbps, the capacity of two such servers is 8 Gbps. Clustering also
provides increased resilience. Clustering can be configured for local on-premises
servers, or for off-premises hybrid premises/Cloud configurations.
Public Internet
If your DEVOS is available to viewers on the public Internet (e.g. home viewers,
consumers, etc.), then you should be concerned about WAN access bandwidth usage.
Your ability to serve many such viewers will be limited by how much public Internet
access capacity you have. For example, if your WAN is limited to 5 Mbps, then you
cannot deliver more than ten 500 Kbps streams to such viewers (and under this
