NBN Co's got a new headache: fixed-wireless congestion

New figures provided by NBN Co to a Senate Estimates committee have revealed that many of the broadband network's fixed wireless towers are oversubscribed, leading to congestion for many rural and regional customers.

When the fixed wireless network was originally being designed back in 2011, the assumed take-up rate (that is, the percentage of premises that qualify for access to the network which actually end up subscribing) was just 20%. In many areas, that appears to have been a significant underestimate, with over a quarter of the network’s 1,972 fixed wireless towers seeing take-up rates of 50% or higher.

NBN Co has declined to identify the specific towers with higher-than-expected take-up rates, with the rationale that “[i]n almost all cases where congestion is occurring, only a portion of a given tower coverage area will be potentially impacted”.

Fixed wireless towers typically contain multiple ‘cells’ which provide the connection between the tower and users. Under Senates Estimates questioning, NBN Co did however clarify that congestion "has predominantly arisen within areas where the fixed wireless service has been available for several years and reflects both high take-up and changing usage patterns”.

“Working to fix the problem”

The fixed wireless network currently has around 240,000 active subscribers – a number which is expected to grow to 400,000 in the near future – and NBN Co has recently changed several aspects of the service, including cancelling the top 100Mbps speed tier and doubling the monthly data quota per user.

In response to the new congestions findings, the government-owned corporation said that it was “working systematically to provide capacity relief across the range of congested cells” and that it was “proactively informing specific households that will be impacted by cell capacity upgrades”.

NBN Co has previously stated that its goal for rural and regional users is to provide a broadband service of at least 25Mbps. A report on IT News estimated that only around 9% of fixed-wireless customers (or just under 22,000) were subscribed to the higher service’s 50Mbps speed tier, which is more expensive that its wired counterpart.