Quality of Service (QoS) in networking is the approach of managing network resources to lower packet loss as well as reduce network jitter. This innovative technology can address resources by assigning the different types of network data at multiple priority levels.
QoS is usually applied on networks that carry resource-intensive information like:
- Video conferencing
- Voice over IP (VoIP)
- Internet Protocol television (IPTV)
- Streamed media
- Online gaming
These sorts of data need to be transmitted in the shortest time frame to be consumable at the receiving end.
Why does network QoS Matter?
Earlier, a business’ network and communication networks were considered as different entities. The phone calls and teleconferences were managed by an RJ11-connector while the calls were monitored by a PABX system. It works differently from the RJ45-connector that used to link laptops, desktops, as well as servers.
When networks carried only data, speed was not so important. Currently, interactive applications that carry both audio and video have to be delivered across networks at high speeds and without packet loss in delivery speeds.
People now make business calls with the support of video-conferencing applications including Skype, Zoom, and Google Meet, which implement the IP transport protocol for sending and receiving video and audio messages.
To know more about the QoS, it is essential to know RTP.
What is RTP?
RTP is a common protocol used in internet telephony communications to handle the real-time transmissions of both audio & video messages. While RTP doesn’t guarantee the delivery of the data packets as this task is managed by switches and routers.
QoS is a hop-by-hop transport configuration applied to the networking devices to make them identify and prioritize RTP packets. Every device between the sender and recipient(s) must be configured to learn that the packet is a “VIP” one and needs to be pushed in the priority lane.
What happens if we don’t go with QoS in networking?
When the RTP packets are not assigned their priorities they will be delivered through default speeds. In a congested network, the packets need to travel along with the rest of the non-urgent packets. While network latency itself won’t have an impact on the quality of the delivered message, it will impact communication between end-users. At 100ms of latency, they will simply talk on top of one another as the packets arrive out of sync.
Real-time applications clear standard transport level buffering, so there is no process to reassemble packets received in the correct order. Jitter is all about the irregular speed of packets on a network. It can end in packets arriving late and out of order.
- Packet Loss
This is the worst-case situation where we find that a number of packets are lost because of too much congestion on the networking devices. When the output queue of switch or router fills up, a tail drop occurs where the device blocks any new incoming packets until space becomes available for packets to receive.
Best Practices to Follow for QoS
There are numerous practices that organizations should implement when determining their QoS requirements.
- Check that maximum bandwidth limits at the sender interface and security policy are not set too low to avoid any excessive packet discard.
- Identify the ratio at which packets are distributed between existing queues and which queues are used by which services. This surely impacts the latency levels, queue distribution, as well as packet assignment.
- Only place bandwidth ensures specific services. This will clear the possibility of all traffic using the same queue in high-volume scenarios.
- Configure prioritization for all traffic through either type of service-based priority or security policy priority, not both. This will ease the analysis and troubleshooting work.
- Try to reduce the complexity of QoS configuration to guarantee high performance.
- To avail of accurate testing results, implement User Datagram Protocol (UDP), and do not oversubscribe bandwidth throughput.
What are the benefits of QoS?
The main advantage of QoS is that it guarantees the availability of an organization’s network and the applications running on that network. It offers a safe, efficient transfer of information over that network. It also permits organizations to use their current bandwidths more efficiently, rather than upgrading network infrastructure to expand bandwidth.
A wide array of benefits include:
- Mission-critical applications have complete access to the resources they need.
- Easy for the administrators to manage traffic better.
- Organizations can lower costs by removing the need to buy new network infrastructure.
By following QoS mechanisms, network administrators can implement existing resources in an efficient manner and ensure the required level of service without expanding or over-provisioning their networks. Essentially, QoS avoid network congestion by prioritizing business-critical traffic to ensure business run efficiently.
Chandan Kumar is working with a top-rated IT & Networking Company, OrangeMantra as a senior network engineer. With years of experience and expertise in Network architecture design & development, you can avail the latest information on innovative technologies similar to what is QoS in this blog post. Stay connected for more posts in the future and comments us for improvements.