Best practtice AppleTVs / mDNS Multicast / Unicast?

[a_huerzeler]

Hello everyone, we switched to the newest version of the Hivemanager local appliance. There is new features available for mDNS and Multicast steering (e.g., Convert IP Multicast to Unicast). We are an MSP in the Education sector with a lot of Apple devices and AppleTVs. What settings are suggested in large networks with AppleTVs?

Thanks for any input.

Andi

[JA]

Hi Sam

I was asking more out of curiosity as we keep adding more Apple TVs, etc. Our current average seems to be about 35% each for Unicast and Multicast and 30% for Broadcast. I will look into some packet captures.

Thanks

[samantha_lynn]

Hi J,

The default thresholds for auto conversation for mutlicast to unicast traffic typically work well for most networks in my experience. That would mean you would see multicast traffic until the channel utilization threshold reached 60, and after that it would use unicast until the channel utilization threshold dropped below 60 again. The same goes for the default client count, although that can go a bit higher without much change in my experience.

In general, multicast traffic isn't a problem unless you have too much of it, in which case switching over to unicast will help clean up your air space and reduce packet damage.

Looking at a packet capture will help you determine if a majority of your traffic is broadcast/multicast traffic. If you find that you do have a lot, and are experiencing other symptoms of wireless issues like slow wifi or frequent disconnections, then you might want to lower the threshold for switching to unicast traffic by 10 or so, and then see how the network reacts for a couple hours before adjusting further.

I hope that helps, I'm sorry I don't have a lot of specifics for you, but please let me know if I can clarify anything. If you'd like to send me a packet capture from your network at communityhelp@aerohive.com, I can let you know what I see there as well and maybe give some more specific suggestions.

[samantha_lynn]

Thanks for the packet capture and tech data. I've sent you the MAC address of a client device that is sending twice as much traffic as the next leading client via email, I'd be interested to see if that's a client you would expect a lot of traffic from in comparison with your other devices.

Based on the rest of your data, I'd recommend setting the channel utilization threshold for mutlicast to unicast conversion to 20-30 instead of the default 60.

That said, I'm hesitant to recommend anything until I know more about what you mean when you say multicast to unicast conversion caused too many performance issues for you (from your email). Could you elaborate on that please?

[JA]

Hi Sam

I realize all situations are a bit different but is there a rough guideline of what a good, or bad, unicast/multicast/broadcast mix should look like?

Thanks