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NBX V3000 MOH

dlefever
Occasional Visitor

NBX V3000 MOH

I have a client that is using a V3000 for their phone system.  It is multicasting to 01:e0:bb:00:00:15 24/7.  The installation guide states that this MAC address refers to the music on hold.  Is this normal? I have not worked with this specific system before, but it seems that it shouldn't flood the network with a few hundred packets per second.



Thank you in advance,



Dale Lefever

14 REPLIES
merlin_1
Super Advisor

Re: NBX V3000 MOH

Multicast broadcasts are all normal for the NBX . We use that mac address to send out our music on hold packets .



dlefever
Occasional Visitor

Re: NBX V3000 MOH

 So it is normal that all my activity lights on 4 switches (connected to phones and PCs) are flashing all the time?



merlin_1
Super Advisor

Re: NBX V3000 MOH

Yes . The switches think its a storm but it is not . Known issue with the NBX and Multicast on the network since day 1 (2000 ? ) , or somewhere near that date .



 



PM me with your email and I will send you a doc that explains the NBX on a data network .



This message was edited by merlin on 3-10-10 @ 2:33 PM
dig1234
Advisor

Re: NBX V3000 MOH

This never made any sense to me, Why in the world does the MOH need to broadcast to the LAN! Hold music is for the NBX to play to callers on the line cards, makes absolutely no sense to broadcast that all over the LAN.



merlin_1
Super Advisor

Re: NBX V3000 MOH

The NBX architecture uses ethernet packets to talk to all devices , including the music portion ( elvis ) of the box . When the NBX sends out music on hold , it is in the form of ethernet packets to other devices like the NCP and the PRI channels . This is accomplished by using 01e0bb000015 type of mac addresses for Multicast in layer 2 traffic . Hence the broadcast out of the NBX into the network  via multicast traffic . Standard IGMP / Multicast network  / settings apply  on the layer 2 network portion as well .



 



Hope this helps



 



Send me an email and I'll send you a doc explaining all of this ......



dig1234
Advisor

Re: NBX V3000 MOH

But can anyone explain why the phones need to recieve MOH? That should be kept at the NBX, not ever sent to the phones.



merlin_1
Super Advisor

Re: NBX V3000 MOH

The phones do not receive MOH . When the caller is on hold the NCP sends MOH Multicast to the PRI for MOH . It just happens to be designed for Multicast to work . The pghones do not accept the multicast packets . THe NCP and the PRI channels do  , or whatever device is put on hold accepts the Mcast packets .



 



The PRI channel plays the Multicast packets after receiving them from the network for the on hold music .



 



 



This message was edited by merlin on 3-11-10 @ 8:50 AM
dig1234
Advisor

Re: NBX V3000 MOH

Doesn't the PRI connect to a digital line card which is inside the chasis and hence no need to multicast the MOH packets all over the LAN?!



(We only have analog line cards.)



merlin_1
Super Advisor

Re: NBX V3000 MOH

The design is for a t1/pri card or an analog card to recieve the mcast from the NCP  , so in or out of a chassis they talk the same way , ethernet packets . 



This message was edited by merlin on 3-11-10 @ 2:36 PM
dig1234
Advisor

Re: NBX V3000 MOH

This is a very poor design, causing much unnecesary network traffic. Just bogles the mind.



If I had a better (read: non 3com) switch I could filter out that MAC address from the LAN.



JimC_1
Advisor

Re: NBX V3000 MOH

Warning: if you filter out that MAC address you will lose a lot more than just MOH.



There appear to be a few different misconceptions compared to how I understand the system after about 8 years of working with it.



The MAC that is sending MOH packets is also used to send many other things than just MOH, like status, system state, Date/Time, new device polling/detection, and some other things. Filter it out and several things will quit.



You are correct in that the (T1/PRI/digital line card) plays MOH to outside callers, but on a v3000 there is no place to install that card within the v3000 itself - the card is in an external chassis communicated with across the LAN by these packets.



When an ext to ext call is put on hold, it is the phone that plays the music to the caller on hold, not the v3000 as there is no analog or T1 port involved in the conversation.



The activity lights on switches count the number of packets, not the size of the packets.


Essentially 1500 packets of 10 bytes is 1500 detections on the switch, and ten  1500 byte packets is only 10 detections - even though they are the same essential total bandwith.


If you put a good packet or traffic sniffer on the network that can do a percentage comparison by actual packet type you will see that the multicasting by MOH is not a lot of bandwidth, just a lot of tiny packets that the lights have fun with because they don't know any better.



You don't mention how many devices you have on the network segment you are concerned about, nor the speed, but I have had systems that were 100base with over 300 total network devices per network segment without any bandwidth difficulties at all.



I hope this helps to clear up any confusion and prevent difficulties.



Have a good day,


Jim


 



bigmaneric97_1
Frequent Advisor

Re: NBX V3000 MOH

You also have to remember that when you transfer, conference and a couple of other things the NBX uses multicasting until the call is finished being built and then the call uses unicasting between the phones.  There is a lot of unicasting that goes on so the phones can discover each other across the network.

 

Eric

reescharhon
Occasional Visitor

Re: NBX V3000 MOH

Then why with nothing connected to the MOH if it is activated in system wide incoming callers when placed on hold get white noise it's just a hissssssss. When deactivated it stops, if you plug in a music source and reset the NBX v3000 it will play for about a day or so and then the hisssssss comes back.

HP has sent a replacement system but getting everything license's transfered has become a nitemare.

merlin215
Valued Contributor

Re: NBX V3000 MOH

Defintately sounds like an equipment issue . We have seen issues like this in the past .

 

Some things electronic are not infallable .