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What is QoS or Network “Quality of Service”?

by NMS Admin - Last Updated: September 20, 2023

What is QoS or "Network "Quality of Service"

QoS, or “Quality of Service” functionality in your network switching environment is getting to be more and more important as VoIP and voice solutions make their way into office networks.

Cisco’s Jimmy Ray Purser makes QoS easy to wrap your head around in this video Cisco produced:

For those without video or audio access in the office, here’s a written transcript of the QoS overview:

What is QOS Tutorial

What is QoS, and what does it mean to your business? Well, simply, QoS is “Quality of Service”, and it allows me to look at certain types of traffic ‑ certain data types if you will ‑ and make sure that they always get through the network, or they’ve got the best chance of making it end‑to‑end. Quality of Service is really important when it comes to deploying a network, especially if I’m going to run voice over it.

I want to make sure that my voice traffic always gets through to the network, and it allows me to actually set a number, a priority on that traffic, to say that ‑ OK, it tells the switch when it’s actually doing all its internal workings, and it says, “OK, if you get to busy, I need you to make sure that you service this traffic first.”

So let’s say, for example, it’s my voice traffic. “I want to make sure that you drop this other traffic or you don’t process it and you process this voice stuff first.”

And QoS is really valuable for that in defining how my traffic flows in my network. Now, this is something that any small to medium business needs to look at if they’re going to start adding voice on the network.

I don’t think QoS is really that big of a deal if I’m just talking data‑only. If I’m doing data stuff, I’m just transferring that, I’ve got my phones hooked up another way, it just isn’t worth the trouble to run QoS on servers and things of that nature.

But the second I start putting voice on there, then the game starts changing a little bit because I have to actually make sure that I load that up and configure it correctly.

Now, it’s important if you’re a small‑to‑medium business and you have even a chance of looking at an IP voice network that you buy a switch hardware that actually will support QoS and VLAN’s to support this new infrastructure so I can prioritize that and get it through. Very, very important stuff.

I strongly recommend that any new hardware is QoS ready, which most of the stuff is today. But that’s what QoS can actually do for your business. I’m Jimmy Ray Purser. Thanks for joining me today.

QoS FAQs

Why is QoS important?

QoS is important because it helps to ensure that critical applications and services are able to function properly and efficiently, even during periods of high network traffic or congestion. This can help to prevent downtime, improve productivity, and ensure a better user experience.

What are some common applications of QoS?

Some common applications of QoS include voice and video conferencing, online gaming, streaming media, and real-time data transfer.

How does QoS work?

QoS works by prioritizing certain types of network traffic over others based on predefined rules and policies. This can involve allocating more bandwidth or resources to certain types of traffic, or limiting the bandwidth or resources available to less important traffic.

What are some of the challenges of implementing QoS?

Some of the challenges of implementing QoS include determining the appropriate policies and rules to prioritize traffic, ensuring that QoS settings are configured correctly on all devices in the network, and monitoring and adjusting QoS settings as needed to ensure optimal performance.

What are some common QoS protocols?

Some common QoS protocols include Differentiated Services (DiffServ), Resource Reservation Protocol (RSVP), and Traffic Engineering (TE).

How can QoS be used to improve voice and video conferencing quality?

QoS can be used to prioritize voice and video traffic over other types of traffic, such as file transfers or web browsing, to ensure that the quality of the conference is not affected by network congestion or delays.

How can QoS be used to reduce network congestion?

QoS can be used to reduce network congestion by prioritizing critical traffic and limiting the bandwidth available to less important traffic, helping to ensure that the network operates efficiently even during periods of high traffic.

How can QoS be configured on routers and switches?

QoS can be configured on routers and switches by setting up QoS policies and rules that define how traffic is prioritized and allocated resources.