Actually, no. Really, all a QoS enabled device can do is create an access list that looks for specific TCP/IP connections and mangles the TOS bit on the packets. So again, you don't need a QoS enabled device; you just need your VoIP devices to go ahead and set the TOS bit, so your layer 3 device can do the right thing. BTW, outside of setting the TOS bit, you can use to 802.1Q/802.1P assuming your VoIP device is VLAN-enabled and your network devices are VLAN aware.

The VLAN route is really the way to go, but most radios aren't up for it. We have found Canopy to do quite well with VLANs and even maintains a separate VC for high priority VLANs. Of course the CMM is not VLAN aware, which is a bummer.

Just to recap, we use Cisco 6500s and Cisco 3750MEs for our entire network, but we don't have to maintain a single access list on them for VoIP since our VoIP PBX/ATA/phones all know about TOS, and 802.1P.


Rick Smith wrote:

I can't see how having a QOS switch could hurt...with VOIP, QOS in as many places
as possible can only help...

Paul Hendry wrote:

Is the switch likely to be the bottle neck in your network? Surely you want
QoS enabled routers where bandwidth isn't plentiful.

-----Original Message-----
Behalf Of George
Sent: 29 March 2006 03:50
To: WISPA General List
Subject: Re: [WISPA] Switch Recomendation

Thanks matt and larry.
I have a 2512 procurve that we like and a Dell switch as well.

Who makes the Dell switches for Dell?

Guess what I really want is to make sure that those little voice packets get the priority :)


Matt Liotta wrote:
We've found that you don't really need a QoS capable switch. What is more important is for the appropriate COS and TOS bits to be set by the VoIP device(s) in question and have a switch capable of "doing the right thing" with those packets. Every enterprise grade switch we have looked at seems to do the right thing when the bits are set. We've been happy with Dell switchs for example.


George Rogato wrote:

I need a recommendation for a 12 port switch that handles a high amount of packet per second and has qos for voip.
Cost isn't an issue.

Anyone have a suggestion?


WISPA Wireless List:



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