IP Telephony <--> Switching Question

[Raul Armas]

Hi Everybody,

I'm planning to use a regular layer 2 switch (WS-C2960S-48FPS-L) as the edge device for a solution where it will provide connectivity not only to wireless APs but also IP phones. My question is: would that be a mistake considering the level of QoS needed to assure proper IP telephony performance on the network?

I ask this because I have never installed an IP telephony solution and I read somewhere it was necessary to use a Layer 3 Switch.

Thanks,

RA.

[Leo Laohoo]

Who is the VoIP manufacturer?

[Raul Armas]

If you mean the IP phones brand, it hasn't been defined yet. If you mean the central telephone exchange device, is currently Siemens.

[paolo bevilacqua]

For simple LAN based IP telephony, no Layer 3 switch is necessary, and not even QoS.

What is necessary, is that design and implementation are done by a reputable engineer.

[Raul Armas]

Hi Paolo, thanks for answering.

I have knowledge about networking but never has installed an IP Telephony solution. That's why I just want to make sure I'm not missing something.

Do you mean in the case people would need to call outside the LAN (through a gateway or a compatible PBX) I will be needing just the Layer 3 Switch as the core Switch? and the edge Switch could be the same Layer 2?

Thanks.

[paolo bevilacqua]

As above: you do not necessarily need a layer 3 switch. For example one could use a router, or in some cases nothing at all.

[Carlo Poggiarelli]

Hi.
It depends on what kind of ip telephony solution you are adopting.
Usually ip phones does not need to be routed outside the network because the pbx connects them with the outside world PSTN/IP

HTH

Regards

Carlo

Sent from Cisco Technical Support iPhone App

[Raul Armas]

Ok, to consider this question as answered:

Is it optional to use QoS on an IP Telephony environment?

There is no problem at all (if I wish to have QoS) on having Layer 2 edge Switches?

Thanks.

[Carlo Poggiarelli]

In some case QOS is not an optional but in other can be unecessary.If you think that the lan where you are implementing IP Telephony solution that could not be so "busy" you can avoid to configure qos

HTH
Regards

Carlo
HTH
Carlo

Sent from Cisco Technical Support iPhone App

[Raul Armas]

Ok, and the 2nd question?

There is no problem at all (if I wish to have QoS) on having Layer 2 edge Switches?

Thanks.