A question that is commonly asked is – “Can I change the multicast subnet that SVSI uses”? And the answer is “Yes”!
Before we dive into the how, let us look at which subnets are used in SVSI for audio and video traffic.
These values represent non-interleaved multicast streams (N2300 series use interleaved multicast streams and are not part of this addressing range) and stream numbers < 256. Stream numbers >256 require calculating the large stream number (third octet) (covered in the Networked AV Training Course).
- Video: 239.255.37. <stream number>
- Audio: 239.255.165. <stream number>
The subnet range above (in red) is what we are interested in modifying.
Things to consider when choosing a multicast subnet:
Chose an address range between 234.0.0.0-238.255.255.255, this is the largest
unallocated block.
Because there is an overlap of IP Multicast addresses to Ethernet MAC multicast addresses,
any multicast address in the [224-239].0.0.x and [224-239].128.0.x ranges should NOT be
used.
We use AMX’s “N-Able” software to modify the range (downloadable at amx.com).
- Launch N-Able on your PC.
- Make sure your devices have been “discovered” or added and are visible in the “Unit Management” tab.
- Navigate to “Tools” -> “Batch Config” and select “Set Multicast to:” (circled below).
- Enter your desired subnet.
- Select the devices that you wish to modify (red arrow below) and click “ok”
