How to use quality of service for prioritising video calls
Video calls compete with cloud backups, file transfers, streaming and software updates for the same limited internet connection. Quality of Service (QoS) can identify delay-sensitive traffic and give it preferential treatment, reducing frozen screens, robotic audio and dropped calls during busy periods.
QoS is most effective when configured on a router that can inspect, classify and queue traffic. It does not create additional bandwidth, so a saturated or unstable connection may still need an upgrade. For Australian home offices, the main objective is usually to preserve call quality while other devices are uploading large files.
Australia’s NBN includes FTTP, FTTN, HFC and fixed-wireless access, each with different capacity and latency characteristics. NBN Co supplies the network while retailers such as Telstra, Optus, TPG and iiNet sell internet plans over it. Many Australians simply call the service “the NBN”, but fibre-to-the-premises, copper-based FTTN and regional fixed wireless require different QoS settings.
Understand what QoS prioritises
QoS works by examining incoming packets and placing them into queues. A video-conferencing stream can be marked for an expedited queue, while backups and downloads enter a lower-priority queue. When the router’s outgoing link becomes congested, it sends queued priority traffic first while allowing other transfers to continue more slowly.
Priority queueing and traffic shaping solve different problems. Priority queueing determines which packets leave first; shaping caps the total speed of a connection to prevent it overwhelming the available link. A sound configuration often combines a small high-priority queue with weighted scheduling for ordinary traffic, preventing backups from completely starving a call.
QoS operates mainly on traffic passing through the router or managed switch. The internet service provider may discard or change priority markings on its own network, so end-to-end treatment cannot be guaranteed. Local QoS still helps with congestion on the household side of the NBN connection, particularly on FTTN services where the final copper segment can limit upload capacity.
Create practical traffic rules
Begin with the devices used for calls rather than with a long list of application ports. Give each participating computer a stable local IP address through DHCP reservation, then create a rule matching that address and the conferencing traffic generated by it. Device-based rules are generally more reliable because modern applications often use encrypted connections and dynamically assigned ports.
Put specific rules above broad rules. A rule for a laptop running Microsoft Teams should precede a rule covering all video traffic, while a catch-all rule can handle ordinary browsing. Some routers can inspect domain names or application signatures, but this feature varies considerably between models sold through Australian technology retailers.
Leave enough upload headroom for the call itself. Interactive HD video may require only a few megabits per second in each direction, but latency and packet loss become damaging when uploads occupy nearly all available upstream capacity. Pause large Synology NAS backups during meetings if necessary, or give backup traffic a lower priority and cap its maximum speed.
Tune Wi-Fi and internet access
Wireless networks need WMM, or Wi-Fi MultiMedia, enabled so latency-sensitive traffic can compete efficiently for airtime. A 5 GHz or 6 GHz band usually offers cleaner performance than crowded 2.4 GHz networks, although walls and distance can reduce signal strength. Wired Ethernet remains preferable for stationary desktop calls. If congestion seems limited to wireless clients, troubleshooting slow Wi-Fi can help separate Wi-Fi faults from ISP problems.
Bufferbloat is another common cause of poor call quality. On a compatible router, enable smart queue management or use a discipline such as fq_codel or CAKE. Setting upload shaping to roughly 85–90% of the stable measured speed can reduce the delay created by queued data. This figure is a starting point; a lower ceiling may suit an unstable NBN line or fixed-wireless service.
Regional fixed wireless in parts of Western Australia and Queensland can experience variable latency regardless of QoS settings. QoS cannot repair a weak signal or overloaded cell network, so compare performance with a wired connection and keep the ISP’s support details handy. Metres of usable upload and stable latency matter more than a high peak download figure advertised in retail plans.
Check switches cables and local contention
A basic home switch forwards every port equally, while a managed network-security switch may offer per-port queues, traffic classification and access controls. If calls cross such a switch, check whether the conferencing device’s traffic is being marked correctly and whether the uplink towards the router has enough capacity. A congested NAS backup can also create local contention even when the internet link itself is healthy.
Internal Ethernet quality depends on both cable categories and installation. The Cat6 versus Cat6a differences matter mainly for higher-speed uplinks and longer runs through Australian homes. Cat6 normally supports 10 Gbit/s up to about 55 metres, while Cat6a can maintain that speed to 100 metres and support lower-power PoE over greater distances.
Check the negotiated link speed at both ends rather than relying on the label printed on a cable. Damaged connectors, tightly bent cable and poorly seated wall sockets can cause intermittent packet loss. In older homes, inspect the route from the NBN equipment to each room, particularly where Ethernet shares a wall cavity with mains wiring.
Test the setup and keep it working
Test the connection before and after enabling QoS, including while a large upload is running. Record ping latency, jitter, packet loss and available upload capacity, then repeat the test during a video call. The most useful result is not the lowest ping alone, but stable low jitter and the absence of latency spikes when other traffic is active.
Watch the router’s QoS counters to confirm that conferencing packets are entering the intended queue. Keep an eye on whether calls improve when cloud storage synchronisation or NAS backups are active. If priority rules appear active but the call remains unstable, test with another device and a different meeting platform to separate classification errors from Wi-Fi or WAN problems.
Firmware updates can alter queue behaviour, while conferencing platforms may change their network requirements. A broader technology news and guides source can help track relevant platform changes, and scheduled router updates should be applied during quiet periods. Recheck the rules after a major NBN plan change, a new managed switch or a move to a different house.
The most reliable QoS setup is simple: classify the actual call devices, give real-time traffic an appropriately sized priority queue, reserve upstream headroom and limit bulky background transfers. It works best alongside healthy cabling, capable Wi-Fi and a stable NBN service.
The essential point to remember is that QoS prioritises traffic; it does not manufacture bandwidth. Correct classification, adequate capacity and continuous testing are what keep Australian video calls clear when the rest of the household is online.