School Bells

[bdmonsey]

Hi,

I set up in a few schools this Bells on fusion (link) it works like a charm, I recently bumped into this school bells (link) but it requires multicast,

I don't have experience with multicast, is it at all possible to have multicast when server is not on site?

Anyone got experience in this?

 

[Adrian Fretwell]

I don't know much about multicast, but I'm pretty sure you can't do it over the public internet. Multicast routing is different and all the routers in a given path need to know how to handle it in order for it to work.

With UDP, you can do a pseudo multicast by simply firing the same packet to multiple IP addresses/ports.

 

[Dast]

Adrian is correct, you can't multicast over the internet. You could however tunnel multicast over the internet via a vpn, or as Adrian suggested use some kind of relay to forward/replicate the packets.

 

[rkbsimpsipper]

I use school bells with page.lua, using the existing dial plan "*720". It calls every defined extension individually, so it works through NAT. Remove the pin code field in the dial plan. You can only define one extension range, then individual numbers after using a comma as the separator. It is slow though, if the range includes more than 20 stations, the answer time seems to start getting delayed. Can you share your multicast dial method you used on the school bell itself?

condition	destination_number	^\*720$			0	5	true
action	set	caller_id_name=All Page			0	10	true
action	set	caller_id_number=9999			0	15	true
action	set	pin_number=71162103			0	20	false
action	set	destinations=1000-4901			0	25	true
action	set	moderator=false			0	30	true
action	set	mute=true			0	35	true
action	set	set api_hangup_hook=conference page-${destination_number} kick all			0	40	true
action	lua	page.lua			0	45	true

 

[ad5ou]

The device I use most often (due to price) is a SNOM PA-1 but Algo, Cyberdata, and even Valcom all have SIP paging adapters that also act as a multicast transmitter.

With the PA-1 or other similar device, it is a standard call or page dial plan, then the device handles answering and relaying audio via multicast.

 

[rkbsimpsipper]

Oh okay, I though you had a trick to directly dial the mcast address from within the school bells event config. In your scenario it is definitely lan only after that first pa gateway device, you can define a different or the same mcast address for the devices residing on the same lan. Then you could hit device A with page.lua, then re xmit the device a audio down to the devices that are lan local for that site. You will likely need to enable igmp snooping and ip multicast on managed switching to broadcast the multicast audio across a trunk to another switch. I use the fanvil pa2/pa3 for this.