Showing results for 
Search instead for 
Did you mean: 

QoS need some help


Hi to all,

I work for voice and people from data don't have QoS in their network and want me to tell them 5 or 6 points to implement it, I downloaded the design QoS guide and i am reading it but I supposed people here have more experience about this to resume it.

I will really appreciate it.

Best regards,



QoS is a very wide and complicated topic. You will need to be much more specific to receive any type of guidance.


Hi Nick,

Thank you very much.

Here are the points why Data people don't want implement QoS:

I think for WAN is ok but not for LAN.

- connections WAN: the voice traffic among headquarters goes for dedicated circuits, he/she doesn't mix with traffic of data. The QoS is usually used in connections WAN where they are shared for all traffic type (voice and data); in those cases if it is convenient to prioritize the voice traffic, more demanding with the jitter and the retards, but it is not our case. The occupation of the voice circuits is not also preocupante by no means.

- Connection each user's LAN: we have prioritized the voice traffic on that of data so much in each one of each user's ports like in the trunks among switches. In all ways each user has a connection to the switches of 100 dedicated Mb, enough BW for the traffic that generates, so much of voice as of data.

Best regards,


Have a look at the Enterprise QOS Solution reference Network Design guide -

Has a lot of material relating to WAN and LAN QOS, including reasons why your data guys should change their attitude to QOS in general.

Thanks pcameron.

i know the concept about QoS, but here I supposed people with more experience in QoS could resume in 4 o 5 lines to tell Data people to implement in their LAN QoS because they don't want it and I think is important.

Best regards,


Hi Alberto,

If you LAN is not busy, and there is not congestion, you may not need to run it in your LAN.

You would need to analyze your LAN packet delays and jitter, but as long as your jitter is less than 30 ms or so, your delay is less than 100 ms, and there isn't packet loss, you should be alright.

Having QoS on your switching network is also beneficial if something goes wrong (broadcast storm, routing loop, etc), and you can be sure that your voice will not be dropped during this period.


Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: