Backblaze's EU-Central Tier 1 ISP traffic jumped 319% in a quarter, and it can't say why

Backblaze's network set a new traffic record in July 2026, but the oddest number in its Q3 network report is elsewhere: traffic from Tier 1 internet providers in its EU-Central region grew 319% from the previous quarter, and the company says the volume alone does not show which workloads caused it.

The report, published October 22 by network engineering manager Brent Nowak, is the third quarter of comparable data since Backblaze relaunched the series, so it now tracks quarter-over-quarter changes.

Fewer addresses, much heavier flows

Backblaze measures "magnitude" as bits per IP address, a rough gauge of how heavy each flow is. Many addresses sending a lot is easy to spread across providers. A few addresses sending a lot is harder to engineer around.

By that measure, US-East CDN traffic per IP rose 602% quarter over quarter, while US-East CDN volume rose 85%, the largest single cell on its volume heatmap. US-East hosting volume grew 133%, and its magnitude 279%. The EU-Central Tier 1 jump also shows up in magnitude, which Backblaze reads as new, high-impact workflows coming from few endpoints.

Neoclouds keep spreading out

Neoclouds, the GPU-focused cloud providers that serve AI workloads, set records in July, eased in August and rebounded in September. Their traffic grew 58% in US-West and 46% in EU-Central. Backblaze says neocloud flows tend to use fewer, more persistent endpoints, which it links to AI pipelines that hold steady connections between storage and compute.

Hyperscaler traffic peaked mid-year and settled back toward baseline in August and September. The company notes neocloud activity now spans US-East, US-West and EU-Central, which may reflect AI data being spread across more regions.

Bigger pipes, with caveats

Traffic over private network interconnections grew 79% over the year, and transit over internet carriers grew 61%. Backblaze says its standard is moving from dual 100 Gbps links toward multiple 100 Gbps and dense 400 Gbps links to absorb bursty neocloud traffic.

The company stresses that the data is not a proxy for global cloud traffic. A handful of large workflows can move the results, EU shifts may reflect changes in its own customer base, and small regions such as Canada's CA-East show big percentages on small volumes. Whether the EU-Central surge persists is something Backblaze says it will keep watching.