Limit Bandwidth for VLAN to save bandwidth for VOIP phones.

[BradMac]

Setup:  We have a MPLS environment with Cisco 2960 switches at each location.  There are 2 VLAN's configured, one for PC's the other for VOIP phones.  The VOIP phones are powered by PoE (or PoE injector) and have an Ethernet plug to connect the PC's, so our PC's get connectivity through the phone (not the case in all branches but majority of them).  The branches have different Internet speeds ranging from 1.5MB - 10MB and 50MB - 100MB for our main location. 

Issue:  When the branch is using all of their bandwidth either by a PC downloading a big file, HQ uploading/downloading files to branch, user watching videos, etc., the phones call quality suffers.  I am looking for help or to see if it is possible to limit the PC VLAN to only use a certain amount or percentage of the bandwidth so there is some bandwidth saved for the phones.  Or, reverse that and reserve a set amount of bandwidth for the phone VLAN.

I have seen a couple articles mentioning limiting bandwidth to a percentage but I don't see where they mention the PC is connected to the phone.  That makes me wonder if limiting the phone would also limit the PC by proxy?  Also, I have seen that the 2960 series may not support some of the config's I have seen and want to make sure what I am looking to implement is actually possible.  

Thanks in advance!

[Collin Clark]

Yes you can, it's called Quality of Service or QoS.
https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/BranchQoS.html
HTH

[BradMac]

Thank you for the response.  Any way to simplify this article?

[Patrick.Williams]

As stated by @Collin Clark the solution you seek  is end to end QOS, both from the switches perspective as well as your MPLS infrastructure, from a layer2 perspective you will require to implement COS and for your MPLS network differentiated services.

Here are some additional detailed examples that may assist you in your QOS implementation journey.

https://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configuration/guide/fqos_c/qcfdfsrv.html

[BradMac]

Thank you for the additional info.  Is this something you have done in your environment?

[Joseph W. Doherty]

Actually, rather than limiting bandwidth, what you really want to do is priorize your VoIP traffic.

In an environment like MPLS, assuming a multi-point topology, you want to apply QoS on both your equipment's MPLS egress and MPLS vendor's egress to you (the latter requiring MPLS vendor support - many MPLS vendor will provide, as an option).

You mention Internet connections. For those, generally ISPs won't provide you any QoS support, so you do not want to mix your internal traffic (e.g. across a tunnel) with general Internet traffic.