What Is Quality Of Service QoS In Networking

Quality of service (QoS) is the use of mechanisms or technologies that work on a network to control traffic and ensure the performance of critical applications with limited network capacity. It enables organizations to adjust their overall network traffic by prioritizing specific high-performance applications.

QoS is typically applied to networks that carry traffic for resource-intensive systems. Common services for which it is required include internet protocol television (IPTV), online gaming, streaming media, videoconferencing, video on demand (VOD), and Voice over IP (VoIP).

Using QoS in networking, organizations have the ability to optimize the performance of multiple applications on their network and gain visibility into the bit rate, delay, jitter, and packet rate of their network. This ensures they can engineer the traffic on their network and change the way that packets are routed to the internet or other networks to avoid transmission delay. This also ensures that the organization achieves the expected service quality for applications and delivers expected user experiences.

As per the QoS meaning, the key goal is to enable networks and organizations to prioritize traffic, which includes offering dedicated bandwidth, controlled jitter, and lower latency. The technologies used to ensure this are vital to enhancing the performance of business applications, wide-area networks (WANs), and service provider networks.

QoS networking technology works by marking packets to identify service types, then configuring routers to create separate virtual queues for each application, based on their priority. As a result, bandwidth is reserved for critical applications or websites that have been assigned priority access.

QoStechnologies provide capacity and handling allocation to specific flows in network traffic. This enables the network administrator to assign the order in which packets are handled and provide the appropriate amount of bandwidth to each application or traffic flow.

Understanding how QoS network software works is reliant on defining the various types of traffic that it measures. These are:

1. Bandwidth: The speed of a link. QoS can tell a router how to use bandwidth. For example, assigning a certain amount of bandwidth to different queues for different traffic types.
2. Delay: The time it takes for a packet to go from its source to its end destination. This can often be affected by queuing delay, which occurs during times of congestion and a packet waits in a queue before being transmitted. QoS enables organizations to avoid this by creating a priority queue for certain types of traffic.
3. Loss:The amount of data lost as a result of packet loss, which typically occurs due to network congestion. QoS enables organizations to decide which packets to drop in this event.
4. Jitter: The irregular speed of packets on a network as a result of congestion, which can result in packets arriving late and out of sequence. This can cause distortion or gaps in audio and video being delivered.

Implementing QoS begins with an enterprise identifying the types of traffic that are important to them, use high volumes of bandwidth, and/or are sensitive to latency or packet loss.

This helps the organization understand the needs and importance of each traffic type on its network and design an overall approach. For example, some organizations may only need to configure bandwidth limits for specific services, whereas others may need to fully configure interface and security policy bandwidth limits for all their services, as well as prioritize queuing critical services relative to traffic rate.

The organization can then deploy policies that classify traffic and ensure the availability and consistency of its most important applications. Traffic can be classified by port or internet protocol (IP), or through a more sophisticated approach such as by application or user.

Bandwidth management and queuing tools are then assigned roles to handle traffic flow specifically based on the classification they received when they entered the network. This allows for packets within traffic flows to be stored until the network is ready to process them. Priority queuing can also be used to ensure the necessary availability and minimal latency of network performance for important applications and traffic. This is so that the network’s most important activities are not starved of bandwidth by those of lesser priority.

Furthermore, bandwidth management measures and controls traffic flow on the network infrastructure to ensure it does not exceed capacity and prevent congestion. This includes using traffic shaping, a rate-limiting technique that optimizes or guarantees performance and increases usable bandwidth, and scheduling algorithms, which offer several methods for providing bandwidth to specific traffic flows.

Traditional business networks operated as separate entities. Phone calls and teleconferences were handled by one network, while laptops, desktops, servers and other devices connected to another. They rarely crossed paths, unless a computer used a telephone line to access the internet.

When networks only carried data, speed was not overly critical. But now, interactive applications carrying audio and video content need to be delivered at high speed, without packet loss or variations in delivery speed.

QoS is particularly important to guarantee the high performance of critical applications that require high bandwidth for real-time traffic. For example, it helps businesses to prioritize the performance of “inelastic” applications that often have minimum bandwidth requirements, maximum latency limits, and high sensitivity to jitter and latency, such as VoIP and videoconferencing.

QoS helps businesses prevent the delay of these sensitive applications, ensuring they perform to the level that users require. For example, lost packets could cause a delay to the stream, which results in the sound and video quality of a videoconference call to become choppy and indecipherable.

QoS is increasingly important as network performance requirements adapt to the growing number of people using them. The latest online applications and services require vast amounts of bandwidth and network performance, and users demand they offer high performance at all times. Organizations, therefore, need to deploy techniques and technologies that guarantee the best possible service.

QoS is also becoming increasingly important as the Internet of Things (IoT) continues to come to maturity. For example, in the manufacturing sector, machines now leverage networks to provide real-time status updates on any potential issues. Therefore, any delay in feedback could cause highly costly mistakes in IoT networking. QoS enables the data stream to take priority in the network and ensures that the information flows as quickly as possible.

Cities are now filled with smart sensors that are vital to running large-scale IoT projects such as smart buildings. The data collected and analyzed, such as humidity and temperature data, is often highly time-sensitive and needs to be identified, marked, and queued appropriately.