ASIC's and Multicast

[Geeky907]

Currently im managing a Rapidly growing Digital 2-way radio system for my employer, all of our repeater sites are AC/DC sites, and ive been a HUGE netonix fan for several years now!...

However, just this weekend i ran into an weird situation... Currently i have a WS12-150dc running my master radio site, and i was growing from 3 repeaters <on ports 1-3> and adding 4 more repeaters destined to be on ports 4-7 <uplink on 12> what i discovered is no matter what combination of repeaters i used and they are EXTREMELY multicast heavy i could only get 4 <any 4> to work on ports 1-4 any attempt to use any other combination of ports resulted in whatever unit was plugged in beyond 4 to be unable to interact. there was traffic moving, however it would only work if the system was at "dead silent" <no radio calls crossing the system, all user idle>

One of my co-workers mentioned that he suspected it had to do with the ASIC per Port and/or switching fabric between Asic's .... i've had Super-Cheap SoHo unmanaged switches handle this kind of load with up to 7 repeaters before <however only for a few months before they started causing problems> ..

Im just wondering if what im dealing with IS an ASIC per port issue? and if there's another Netonix DC switch that would be more favorable for this load... the radio system manufacturer recommends HP or Juniper switches, which pose their own power hurdles in my specific application.

Thanks in advance for any advice and info!

- Mike

[Stephen]

I know the WS switches can run at line speed without much trouble but lots and lots of multicast does present somewhat of a different animal for the switch to deal with.

First things first, are you using the latest firmware? There have been a lot of fixes that may increase stability and increase throughput further increasing the likelihood it will handle the load.

There are others on this forum with more networking experience as a whole who may have better suggestions but these are the things that go through my head that might be helpful:

Have you tried using IGMP Snooping? That might reduce the load from the multicast packets enough for the switch to be able to handle it.

Could you use VLANs to limit the domain size for the multicast packets and just put 2 ports into each vlan for the radio's to pass through?

If not, could you potentially split the load between 2 smaller switches? Maybe 2 WS-6-MINI's
could divvy up the load a bit easier with a single link between them.


But as far as ASIC's go, all WS series use the same switchcore technically so if it's just beyond what it's capable of dealing with then you would need a more powerful switch.

The new WS3-14-600-DC does have a stronger core than the WS series, but beware they are still in beta. Might be worth a try though depending on your budget.

[Geeky907]

Running firmware 1.5.8 unfortunately all the repeaters need to be in the same vlan so they can jabber at eachother…

[sakita]

Is the limit something to do with the number of packets per second? In other words, do the radios multicast out a large quantity of small packets continuously?

I do know of Juniper equipment being used in a network that includes mobile radios and am curious as to what the performance difference might be.