The Basics of QoS and Network Performance

Have you ever been in a meeting online and found that the host (or your own) voice and video quality left much to be desired? In this age of all things digital, QoS is incredibly important to provide a superior experience for employees and clients. A NetOps team needs deep insights into the network architecture, policies, and protocols that ensure a successful delivery of business-critical applications.

What is QoS?

QoS ShapingQuality of Service (QoS) is a suite of technologies utilized to manage bandwidth usage as data crosses computer networks. Its most common use is for the protection of real-time and high priority data applications in converged networks. All network infrastructure devices have limits on the amount of traffic that can flow through them. Quality of Service (QoS) management is the collection of mechanisms that control how traffic is prioritized and handled during these times.

Why is QoS in Networking Important?

There was a time, perhaps not too long ago, when networks carried only data – and thus there was not too many critical applications that were utilizing it, making speed optimization not a big problem for NetOps teams. However, with the advance of video-conferencing applications like Zoom or Cisco Webex, speed and quality of such applications have become increasingly important to the business.

Applications are critical to keeping an enterprise running at optimal levels. Without having QoS configured properly within the network there can be issues with latency, jitters, and packet loss. QoS is incredibly important for high-bandwidth, real-time traffic which impacts how well the network can manage the aforementioned applications and more.

How Does QoS Work?

Packet flow through a Typical QoS policyQoS technologies, or tools, each have specific rolls that are used in conjunction with one another to build end-to-end network QoS policies. The two most common QoS tools used to handle traffic are classification and queuing.

Classification identifies and marks traffic to ensure network devices know how to identify and priorities data as it traverses a network. Queues are buffers in devices that hold data to be processed. Queues provide bandwidth reservation and prioritization of traffic as it enters or leaves a network device. If the queues are not emptied (due to higher priority traffic going first), they overflow and drop traffic.

QoS Best Practices

Deploying and designing QoS for the network is an incredibly complex procedure, one that takes proper planning and strategy. We’ve compiled a list of some best practices to keep in mind when designing QoS policies:

  • Choose a matching and marking strategy that ensure traffic is matched and marked effectively and ensure traffic is protected where it is most needed.
  • When possible, follow industry standards when deploying QoS polices to align with service providers and business partners.
  • Mark packets as close to the source as possible (i.e. the device itself or switch connected to the device).
  • Police recreational or scavenger traffic as close to the source as possible to prevent unnecessary bandwidth usage if traffic exceeds a certain threshold.
  • Enable queuing wherever congestion may occur to guarantee service optimum perforce to critical applications. This includes data center and campus LANs as well as public (DMVPN) and private (MPLS) WANs.
  • Provide at least 25% bandwidth for Best Effort traffic in the class-default.

Is Your Business QoS Ready?

Implementing QoS on a network of any size is a complex and time-consuming process. Implementation requires a diverse skill set that encompasses technical and even political skills, project management expertise, patience, and confidence. Proper planning, technical, and project understanding, along with the right network management tools, will help network managers and engineers deploy and maintain converged QoS-enabled networks with less time, money, and stress.

For more information on managing and deploying QoS, read our comprehensive eBook. Ready to take the plunge? Contact LiveAction and learn about how we can assist your organization to deliver a superior user experience.