NetPlay Video network setup:

Operational mode selection:

NetPlay video sends all video data over standard ethernet networks with a data rate of approximately 20Mbps per video stream.  It does not require a dedicated or seperate network.NetPlay video encoders can operate in two distinct modes.  You will select which mode to use in your installation:

  1. Unicast streaming mode
  2. Multicast streaming mode
Mode Max simultaneous displays Min speed switch IGMP required Setup required
Unicast (default) ~16 100Mbps or 1000Mbps N N
Multicast infinite 100Mbps Y Y

In Unicast mode, each VTX will send a unique video data stream directly to the IP address of each VRX which is currently selecting that source.  This mode is preferred for its simplicity (works with all networks/routers/switches with zero config), but cannot be used for systems where more than ~16 TVs will be displaying the same source at the same time.  In practice, this usually means Unicast mode can be used for all residential installations and commercial installation with fewer than 16 TVs.

If Unicast mode is not appropriate for your installation, we will use Multicast mode.  Multicast mode can support any number of sources and displays becauses the routers duplicate the video data stream ONLY AS NEEDED by downstream decoder devices.  This stream duplication happens automatically via the IGMP protocol, so you do not need active control on any of the routers/switches.  It does require switches and routers that support IGMP and these devices must be statically configured to enable that protocol (see instructions below).

Multicast or unicast mode is set in the source configuration page of Virtual Matrix.  While it is possible to use unicast on some VTX sources and multicast on others, there usually is no advantage to doing this.

Unicast networks:

If you are using unicast mode, you only need to make sure that each network leg has sufficient bandwidth to support your streams.  Since each stream is ~20Mbps, a 100Mbps leg should have no more than 4 streams and a 1000Mbps leg no more than 40 streams.

MOCA ethernet over coax is an excellent solution for sending NetPlay video over pre-installed coax wiring.  Each coax network leg is about 150 Mbps using very inexpensive adapters.

Modern ethernet switches and routers will properly route all network traffic so that each decoder will only receive a single stream. 

If you are using a Cisco managed switch, you will want to enable 802.3 flow control.  By default, Cisco managed switches disable flow control and this can lead to "tail drops" which result in picture artifacts.  This is done under "Port management" - "Port settings".  Select each port that will be connected to an ENCODER or DECODER and select "Edit".  In the Edit dialog set "Flow Control" to "Enable".  Also enable flow control on any ports which go to other switches which have NetPlay devices attached.

Multicast networks:

For multicast networks to function properly, you need to meet the following criteria on the portians of the network that will carry NetPlay video multicast streams.

You entire network does not need to be multicast capable, just the network legs / switches that carry NetPlay video data from encoders to decoders.  However, it is important to make sure that multicast traffic is not broadcasted to the portians of your network with is not multicast capable. 

An IGMP capable switch will handle multicast traffic as:

  1. If a port has a registered listener for the multicast stream, that stream will be duplicated and sent to that port.
  2. If the switch receives a multicast stream with no listeners ("unregistered multicast"), the default behavior is to forward this stream to ALL ports.  It is important to set "filter unregistered multicast" on any port going to non-multicast capable sections of your network.

A non-IGMP switch will handle multicast traffic by treating it as BROADCAST and sending to all ports.  This can be ok for small downstream switches, but should never be allowed on your main router or wireless bridges (if using any multicast streams).

We recommend using Cisco SG300 switches for multicast.  Make sure they are all on firmware 1.3.7.18 or later.

Multicast RTSP for wireless video

Multicast RTSP can be used (when the proper license is purchased) to enable streaming to a large number of mobile clients simultaneously.  If using this feature, we recommend using a high quality wireless access point (such as a Cisco WLC).  There are many WAP settings that effect wireless performance for multicasting.  At a minimum, you must have multicast enabled (IGMP snooping) and sufficient bandwidth allocated for multicast traffic.  You may also need to allocate WMM or use Cisco VideoStream options for the best performance.

When using multicast RTSP be very sure that you filter unregistered multicast on networks ports that should not carry video data.