Basic QoS questions

[Andy White]

Hello,

Out company is finally going to install VOIP, they will be using something called Natterbox, but I've been asked to add QoS to our Cisco switches and routers in various locations I will also need to add a second VLAN for voice I believe which is ok.

1. How can we configure QoS so VOIP is treated first then video streaming then video?
2. As we will need to add a second VLAN, so I assum all ports to phone swill be truk ports?

Thanks

[Andrey Chertolyas]

Hi Andy,

Regarding your second question - you have to configure voice vlan on your switches. Please refer to this document:

http://www.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.1_19_ea1/configuration/guide/swvoip.html

Edit: actually, this can be irrelevant to your situation since you can use non-cisco ip-phones, if I understood you right.

As for your QoS question - could you provide more information about your task? What do you want to get as result? If I understand correctly, Natterbox is a cloud-based IP PBX which is hosted somewhere outside of your network, is it correct?

Kind regards,
Andrew C.

[Andy White]

Hello,

Natterbox recommend dual VLANs for their soft and desk phones, but yes it is cloud based, but requires QoS everywhere.  We have an MPLS where we have a connection to Natterbox, so none goes over the Internet.

Thanks

[Andrey Chertolyas]

Hi Andy,

Actually, if there is no oversubscription on your WAN links and you have enough bandwidth for the number of simultaneous calls you need you may not require the QoS configuration at the moment, but that's not a good advice, though.

The good idea is to make the complex analysis of your network to create QoS design-plan which will cover your needs.

Kind regards,
Andrew C.

[Ayodeji Okanlawon]

Andy,

To start, you need to understand how the soft phone and desk phones mark voice traffic. Cisco switch and Routers perform QoS by trusting, understanding or marking traffic using DSCP, PHB and port numbers.

Hence questions you need to ask are

1. Do the softphones mark their voice and video traffic? If they do how do they do it?

2. What ports are used for voice traffic?

3. what ports are used for signalling traffic

4.What ports are used for video traffic if its differs from ports used for voice.

Once these facts are understood, you can beging to look at how to configure your switches and routers based on this parameters

Please rate all useful posts

"opportunity is a haughty goddess who waste no time with those who are unprepared"