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MX-ONE on separate network from IP phones

MX-ONE on separate network from IP phones

Hello everyone.
A question on the correct configuration of the LAN between the MX-ONE PABX and IP phones.

I example:

The PBX has the address with all its cards and phones instead are on lan
Logically there is a firewall that is routing between the two networks.

like this configuration , or the phones and PBX on the same LAN

Thanks for the eventual answer.


Miran Piscanc

RE: MX-ONE on separate network from IP phones

It is standard to have handsets on a different subnet behind a firewall, just make sure you have the correct ports open, the routing is correct and you have QOS/VLANs

Best parnum

RE: MX-ONE on separate network from IP phones

I understand, however, if the firewall fails to properly handle packets for routing between the two VLAN, defined as packet send time, because busy managing well over 100 with fairly consistent VLAN data traffic, and countless Nat rules and VPN this means that sometimes the phones are not reachable immediately call (congestion), then still I do not understand, because the pbx must stand on another VLAN than telephones.
I have recently install and I plan PBX Ericsson UCS100 full IP, and configure the PBX and phones on the same network and I never had problems of congestion or inaccessibility of telephones.
Who gives me a valid reason to install an MX-One of its different VLAN?



Miran Piscanc

RE: MX-ONE on separate network from IP phones

So you are saying your Lan/Wan is not correctly ready or configured for VoiP? What makes you think it is your firewall rather than a router? Have you performed network readiness testing?

Best parnum

RE: MX-ONE on separate network from IP phones

yes, but the question that I make is: why you write that it is standard to have the phones of different LAN from the pbx?
We make the case that the firewall or router is blocked for any reason (we know that can will happen), if they are on two LAN, PBX and phones do not work, but what can not happen if PBX and phones are on the same LAN.

I want to understand this, because anyone using this way to install a PBX?


Miran Piscanc

RE: MX-ONE on separate network from IP phones

It is standard now to have phones on a different LAN, so I do not understand what you are asking - how do you think an MXOne in a data centre works, or any geographically dispersed installation?

The answer to the difference between then LAN and WAN setups is - is the WAN network tested and ready for VoiP? You presumably have network redundancy so a blocked router should be a concern to your IT dept and the registrations should re-route via an alternate path. If your firewall is a problem get a more appropriate firewall now you have a requirement for VoIP, it's just letting the traffic through, if you have a requirement to do a lot of NATing you should consider adding an SBC to do that?

Ultimately the handset and MXOne don't behave any differently if they are on the same or different subnets, the network does,

Best parnum

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