As stronger restrictions around COVID-19 begin to take effect, and many of us contemplate a future of working from home for an extended period, the resilience and capability of our networks takes on an even greater importance. No-one is more aware of that than me, and my network engineering teams at BT.

Over the last few days, I’ve seen a flurry of media stories reflecting an understandable concern that our networks will be unable to cope with the additional traffic of millions of home-workers.

I’d like to share a few facts that might help to address some of these concerns:

The UK is one of the world’s most advanced digital economies, so we overbuild our networks to compensate for our love of high-definition streaming content, video gaming and other bandwidth-hungry applications. In contrast, online conferencing services, even video-calls, consume far less bandwidth.

The UK’s fixed broadband network core is built (with a lot of ‘headroom’) to support the ‘evening peak’ of network traffic, driven by these high-bandwidth applications. The highest peak we’ve seen in evening traffic was 17.5Tb/s, driven by videogame updates and streaming football.

In contrast, daytime usage, during working hours, generally runs at about 5 Tb/s.

Since Tuesday this week, as people started to work from home more extensively, we’ve seen weekday daytime traffic increase 35-60% compared with similar days on the fixed network, peaking at 7.5Tb/s.

This is still only around half the average evening peak, and nowhere near the 17.5 Tb/s we have proved the network can handle.

These facts give us confidence that the additional load on the broadband network is well within manageable limits and we have plenty of headroom for it to grow still further.

But we’re not complacent. We’re monitoring the network closely, and collaborating with the other UK networks and content companies. Our Network Operations Centre teams are operating around the clock to identify any issues and resolve them as rapidly as possible. And if more capacity is needed, our engineers are on standby 24/7 to make that happen.

Because we’re monitoring the network so closely, we’re noticing a few changes to usage patterns as a result of COVID-19 that I’d like to share:

We’re actually seeing a 5% decrease in mobile data traffic, as a lot of people are connecting their mobiles to their home WiFi, rather than using the cellular network.

Data usage is peaking at around 5PM, the time of the Prime Minister’s daily briefing.

Mobile traffic is becoming more evenly distributed across the country, as people travel into urban hubs less frequently.

Roaming traffic is falling by about 10% per day, with a 55% drop over the last 5 days.

We are seeing an increase in mobile voice call volumes, which is to be expected. This is well within the levels the network is built to handle, but we would encourage customers to use the landline or IP voice services like Skype as well, especially for long conference calls.

Organisations are also seeing increased numbers of connections into their corporate Virtual Private Networks (VPNs) and conferencing services. This may mean that companies need to think about how they optimise use of these private networks, or increase their provision of such services.

In conclusion, the COVID-19 outbreak is causing changes to the way our networks are being used. At BT, we’re monitoring those changes carefully to make sure we can respond rapidly if needed. However the UK’s communications infrastructure is well within its capacity limits, and has significant headroom for growth in demand. Our networks have never played a more critical role, and I couldn’t be more proud of the hard work my teams are putting in to keep the country online during this difficult time.

- Howard Watson, Chief Technology and Information Officer

For more information about what we’re doing in response to Coronavirus, please visit:

BT Group: www.btplc.com/coronavirus

BT: www.bt.com/coronavirus

EE: www.ee.co.uk/coronavirus

Plusnet: www.plusnet.co.uk/coronavirus