Hello,
I have 3 multicast subnets, each has about 55mbps bandwidth and 10 iptv stb’s with 100mbps ethernet card (MAG254).
If I put all subnets in 1 switch I have about 150mbps bandwidth, which is to much for the stb. Is it posible to route these 3 subnets, that the stb’s has access to this subnets and will not overflow the bandwidth of the stb?
Here is the schema of the network.
Hope you understand what I mean 
Have a nice weekend.
Rok
Between Routerboard and STB, add a switch which allows IGMP snooping and enable for all ports. Connect Routerboard and new switch together with Gigabit and it will only peak max 150mbit/sec as 3x 50mbit. the switch backplane and cpu handles the distribution so less worry.
If you need to expand, use switches with dual gigabit uplink ports and connect together. Do not create a loop though - daisy chain them but don’t connect last switch back to first switch again.
edit: the igmp snooping will automatically ‘turn’ on and off the multicast streams to each stb as each stb changes streams. as long as the stb sends the correct igmp packets.
edit edit: or just enable igmp snooping on you existing switches.
Tony
Hello,
Tony thank you for your answer. Your answer in correct. I already found the sollution and the system is working whithout any problems.
It took some time, that I found out, mikrotik is not supporting igmp snooping 
Greetings, Rok