From a software standpoint, quality of service (QoS) involves the measurement of key performance, reliability, availability, scalability, and related metrics to gauge how well a service is running. Such QoS measurements therefore have an overarching networking component—since application performance and network performance are so closely related.
How we define quality of service differs from one use case to another. For example, we often analyze datagram delivery rates and latency while evaluating UDP applications. You cannot observe high UDP quality of service while also experiencing notable packet loss, added latency, network bandwidth limitations, or network jitter. These types of issues can wreak havoc on real-time applications.
The overall goal is to optimize our applications and networks in ways that promote rapid, reliable, and high-throughput traffic processing to enable seamless user experiences.
Why is quality of service (QoS) important?
In short, users enjoy using applications that perform as expected, while organizations want to deliver excellent, interruption-free user experiences. This is true for eCommerce platforms, productivity tools, and anything in between.
There are also major incentives—especially in competitive industries such as media streaming—to retain users through superior service availability and performance. A company's reputation depends on popular perception of their UX. After all, 88% of internet users are less likely to revisit a website following a poor user experience. Service providers often get one chance to impress.
Performance and reliability improvements directly support these goals. A deep dive into QoS can result in better traffic prioritization and distribution, reduced resource use, lower latency, improved packet delivery, and more comprehensive CDN or ADN coverage.
What does good quality of service (QoS) look like?
Quality of service often rests on a number of factors—namely high reliability, low latency, maximum uptime, bandwidth availability, and scalability. It involves understanding not just how an application is running today at baseline, but also how that application (and the supporting network) will respond to sustained or sudden traffic spikes in the future. If any application is struggling to provide acceptable quality of service, increased activity will only worsen that problem.
Envision a video conference call. You'll likely notice when another participant's video feed is buffering, choppy, or otherwise low quality. Conversely, when a video call functions as expected, participants won't dwell on performance or reliability issues because they're simply not happening.
This plays into the idea that good QoS isn't always "noticeable" in the same way as poor QoS. If anything, good quality of service (from a user's perspective) is about consuming a service without worrying about hiccups. Because negative experiences are so memorable, this overall perception depends on establishing long-term patterns of reliability. It's the difference between thinking "this is a bad infrastructure day" and lamenting "this app never works how it should."
How can organizations ensure higher quality of service (QoS)?
All discussions on assessing and improving QoS should include ample planning. This involves understanding your traffic profile, your application's infrastructure requirements, and the vast variety in real-world networking performance. Organizations should ask themselves the following questions:
Where does the majority of our traffic originate, and do we have the necessary edge locations to deliver applications seamlessly?
How much baseline traffic do our services generate?
How much bandwidth is needed to support these services?
How much web server or database capacity do we have?
Do any services routinely experience packet loss or congestion?
Based on the answers to the above, an organization can better understand its infrastructure strengths, weaknesses, and form a plan to address any shortcomings. This can involve a lot of administrative effort and plenty of manual configuration.
Alternatively, many organizations offload many such tasks to external vendors. Load balancers, reverse proxies, and other networking equipment can help organizations better manage application QoS. Application acceleration features such as compression, connection pooling, and TLS termination (to name a few) can have a large impact. Similarly, high availability features can help applications stay online—even under adverse conditions—and exert strain on backend resources.
Plus, what defines "good" quality of service can differ. While chasing fine-nines availability is an admirable goal, data-driven teams can assess historical application performance metrics and weigh current performance versus expectations.
Does HAProxy help improve quality of service (QoS)?
Yes! HAProxy includes a number of application acceleration, high availability, and powerful load balancing features that help applications run their best. This is accomplished by optimizing the entire request-response chain while helping prevent outages.
Meanwhile, HAProxy Fusion compiles over 150 runtime metrics from your HAProxy Enterprise clusters for rich, visually-engaging insights into application performance and security. HAProxy Fusion's customizable dashboards help you centrally monitor the QoS drivers that matter most to your organization and helps teams act decisively to solve issues.
To learn more about QoS support in HAProxy, check out our HAProxy Enterprise datasheet, our high availability solution page, or our network performance documentation.
