Overview

In a Just Add Power Video Distribution system, Multicast Switching is a method of switching sources that changes the multicast IP of the Decoder — called a Channel — to match the multicast IP of the Encoder it should display.

Channel changes can be triggered in multiple ways depending on the control system or end-user needs.

• Basic Mode: Audio, Video, USB, and Serial all use the same Channel.
• Advanced Mode: Each service can use a unique Channel. All devices in the system must use the same Mode.

Use our AMP Software to set up Just Add Power devices for Multicast Switching.

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Requirements

1. Compatible with Omega, Ultra and MaxColor Series devices
2. justOS firmware B2.1.0 or greater
3. All units on the same VLAN with the same IP scheme

For network setup, see Multicast Switching for Single VLAN Implementations.

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Concept

Audio and video in a Multicast Switching system are distributed according to a stream’s multicast IP. For simpler programming, the multicast IP is represented by a single Channel number.

• Audio and Video use separate multicast IPs, so they can be routed independently.
• Each Encoder has a unique multicast IP on the network.
• A Decoder changes its multicast IP (Channel) to match the Encoder it should receive.

Default Multicast IPs

Basic Mode — audio and video switch together (default)

• Video — 239.92.0.0
• Audio — 239.92.0.0

Advanced Mode — audio and video can switch together or separately

• Video — 239.92.0.0
• Audio — 239.93.0.0
• USB — 239.94.0.0

Multicast IP to Channel Translation

The multicast IP structure defines how Channels are derived:

• The first two octets must be identical across all devices.
  • The first octet may be changed, but must match on every device.
  • The second octet distinguishes services (e.g., Audio vs. Video).
• The last two octets are unique per Encoder and map directly to the Channel number.
• Channel numbers are integers from 0–9999.

Channel	Multicast IP
0000	239.92.00.00
0099	239.92.00.99
0100	239.92.01.00
9999	239.92.99.99

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Basic Mode Commands

AMP Alternate Configuration builds a system in Multicast Basic Mode and applies Channels and Management IPs. Use the following commands only if you are not running AMP.

All commands are case-sensitive.

Set Basic Mode (default)

Set once. All devices must use the same Mode. All services switch together.

channel mode basic

Set Audio & Video Channel

Set once on an Encoder. Send to a Decoder to switch audio and video. Replace $ChannelNumber with 0–9999.

channel $ChannelNumber

Set Management IP (Encoder & Decoder)

Sets IP address, subnet mask, and default gateway. Example:

astparam s ip_mode static;astparam s ipaddr 172.17.128.1;astparam s netmask 255.255.0.0;astparam s gatewayip 172.17.255.254;astparam save

Note: Use PuTTY or Windows Telnet to send the string. Do not use the webUI of an Encoder or Decoder.

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Advanced Mode Commands

AMP Alternate Configuration creates systems in Basic Mode. You can keep existing Management IPs, but converting to Advanced Mode is manual.

All commands are case-sensitive.

Set Advanced Mode

Set once. All devices must use the same Mode. Allows each service to switch separately. Reboot required after sending this command.

channel mode advanced

Set Audio Channel

Set once on an Encoder. Send to a Decoder to switch audio. Replace $ChannelNumber with 0–9999.

channel -a $ChannelNumber

Set Video Channel

Set once on an Encoder. Send to a Decoder to switch video. Replace $ChannelNumber with 0–9999.

channel -v $ChannelNumber

Set USB Channel

Set once on an Encoder. Send to a Decoder to switch USB control. Replace $ChannelNumber with 0–9999.

channel -u $ChannelNumber

Set Management IP (Encoder & Decoder)

Example static configuration:

astparam s ip_mode static;astparam s ipaddr 172.17.128.1;astparam s netmask 255.255.0.0;astparam s gatewayip 172.17.255.254;astparam save

Note: Use PuTTY or Windows Telnet to send the string. Do not use the webUI of an Encoder or Decoder.

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HTTP API

The full HTTP API for justOS is available here.

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Web Interface

The Web Interface allows Basic Mode configuration only.

Set Audio & Video Channel

Set once on an Encoder. Send to a Decoder to switch audio and video. Replace $ChannelNumber with 0–9999.

On the Network tab, set the Multicast Channel and select Apply. The Channel updates immediately.

Set Management IP (Encoder & Decoder)

On the Network tab, set IP address, subnet mask, and default gateway. Example: IP 172.17.128.1, mask 255.255.0.0, gateway 172.17.255.254.