By: John Shepler

Modern networks are typically converged, meaning they handle various traffic types like backups, file transfers, cloud access, VoIP calls, streaming, and web services. This begs the question: how can we ensure these networks maintain the integrity of each process with so much going on?

The Need for QoS

When we implement Quality of Service (QoS) controls, a network becomes more than just a passive conduit. But why is this necessary? Why not simply provide enough bandwidth to accommodate all traffic without limitations?

While possible, this approach can be extremely expensive. Whether it’s 10 Gbps, 100 Gbps, or even 1 Tbps, achieving a bandwidth level that effortlessly handles all traffic comes at a significant cost. On local networks, even existing fiber infrastructure might prove insufficient. When considering MAN and WAN bandwidth, the expenses can be especially daunting.

Different Applications, Different Requirements

This is where QoS controls become essential. Not every data transfer requires lightning-fast speeds. Overnight backups don’t need to finish in minutes, and emails don’t need instant delivery. Even large video downloads are expected to take some time.

However, we do demand clear and uninterrupted phone calls, smooth video conferencing experiences, and responsive cloud software, free from delays or lag.

The key takeaway is that not all data packets are created equal. Some need immediate prioritization and the fastest possible delivery, while others can afford to wait.

CoS to Implement QoS

We need a traffic management system that intelligently allocates network capacity among competing data packets. This process is called Quality of Service, and the mechanism enabling it is Class of Service (CoS).

CoS is a numerical tag embedded within the Ethernet header. With three bits allocated, it allows for eight potential classes (0 to 7). In practice, we usually don’t need all eight. A few distinct classes are typically sufficient to prevent less time-sensitive traffic from impacting high-priority traffic.

Your local network likely already utilizes CoS tags, particularly if you’ve transitioned from analog to VoIP phones. This is because voice traffic and large file transfers, unless separated, can negatively impact each other.

Imagine CoS tags as lane assignments on a highway: voice packets travel in the high-occupancy lane, cloud traffic gets the fast lane, and backups are relegated to the slower right lane. CoS determines which lane each data packet uses.

The Next Step: Dynamic CoS

As network conditions change, so too might the need to adjust class assignments. While local IT staff can implement these changes on internal networks, making modifications to the WAN is often more complex. Legacy processes for WAN changes often involve paperwork and can take weeks to implement.

tw telecom has introduced Dynamic CoS, enabling customers to prioritize applications dynamically and in real-time. Combined with dynamic bandwidth control, this empowers users with extensive control over WAN resources as if they were part of their own network.

If you need more adaptable bandwidth solutions capable of responding to evolving business needs, exploring new intelligent and dynamic network services could be beneficial. Discover the range of MAN and WAN network services that align with your specific requirements.