High Speed Hybrid Speed Boost

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June 24, 2022

By Graham Turnbull

The launch of BT’s Hybrid Speed Boost powered by Tessares has received a lot of media attention. Fierce Telecoms wrote an excellent summary of our fixed / mobile hybrid use case and who could benefit from it. The BT proposition is currently just for business customers on ADSL (<20 Mbps down < 1 Mbps up), but the solution works equally well on higher speed broadband lines.


High Speed Hybrid Speed Boost Use Case

We already have customers using our solution to boost speeds beyond 100 Mbps using a combination of VDSL and 4G. This is sometimes to boost speeds to the advertised speed as in the case of Go-Malta, or it is used to differentiate from other providers’ offerings in the case of Telia.  

Even in areas where the fibre to the cabinet (FTTC) penetration is very high, speeds vary with distance from the cabinet. Half of the speed is lost in the first 750m.  Broadband customers have traditionally paid a premium for additional speed but this speed is simply not available beyond 750m.  BT’s premium SOGEA / FTTC product is only available to customers less than 450m from the cabinet.

VDSL Speed Drops off sharply with distance from street cabinet

Fig 1 – VDSL drops off sharply with distance from speed cabinet. Source: https://www.increasebroadbandspeed.co.uk/chart-of-bt-fttc-vdsl2-speed-against-distance-from-the-cabinet


Aggregate Bandwidth Limiter

Our solution can boost speeds to the advertised speed (e.g. 72 Mbps) just for the customers who need it and our Aggregate Bandwidth Limiter (ABL) can ensure that the advertised speed limit is not exceeded. This is intelligently accomplished by using the mobile network only when necessary and in such a way as to not interfere with other (mobile) users. Mobile users always have a higher priority and we find that fixed and mobile users need the mobile network at different times of the day.

One of our operators limited the amount of mobile network bandwidth per customer but they have since removed this and implemented our ABL feature instead. Another customer is thinking about removing the mobile network cap entirely because the service is having no negative impact on the mobile network. 

ABL allows the full portfolio of speed tiers to be offered to more customers.


Aggregate Bandwidth Limiter allows you to cap speeds at the advertised limit.

Fig 2 – Tessares’ ABL feature makes it possible to set maximum download speeds to limit the use of the 4G network. Customers receive the ‘up to’ or advertised speed.

The Marketing of Speed

Speed is not the only factor in determining the quality of the customer experience but speed is still used by customers in their decision making. Indeed, in countries where there is a national broadband network, Australia for example, every retailer is reselling the same network. Their ability to meet the network demand of their customers is an important differentiator and the Australian market is full of speed comparison websites based on quarterly performance reports (link to latest ACCC report). In order to top the league table in Australia, a retailer has to buy more capacity than necessary (or at least more capacity than their competitors)  but margins, especially on <100 Mbps products, are very thin.

Australian ISPs competing on speed even though they all use the NBN

Fig 3 – Australian NBN RSPs compete on speed but they all use the same network. Reaching 100% of plan speed (or more) requires buying more capacity.


What Hybrid speeds are possible?

The possible speeds vary based on the network inputs, usually about 95% of the combined DSL and 4G speeds. The 4G network obviously varies from place to place and by time of day. In our real world experience we are seeing a 72 Mbps line boosted to 104 Mbps and a 36 Mbps line getting double the usual speed. 


Hybrid Speed boost on 36 Mbps VDSL line


Chart showing the speed boost from hybrid access on a 36 Mbps VDSL line

Fig 4 – Daily average of two months of speed tests. 36 Mbps VDSL line showing impact of 4G speed boost. Download speed was doubled. Average of daily means 71.4 Mbps


Hybrid Speed boost on 72 Mbps VDSL line


High Speed Hybrid Speed Boost on 72 Mbps VDSL line

Fig 5 – 12 days of hourly speed tests daily average on a 72 Mbps VDSL line showing impact of 4G speed boost. Download speed was boosted by 34 Mbps. This represents a 50% boost. Note that the maximum amount of boost was being capped by the mobile network.


The Business Case for Hybrid Access

Doubling the download speed from 36 Mbps to 72 Mbps is worth £5.00 per month in the UK or £120.00 over the life of a 24 month contract. Most of the cost of deploying this solution is in providing the 4G modem. The same  4G modem can also be used to instantly provision new customers and provide ‘unbreakable’ broadband. In the UK this service retails for £7 per month or £168 over the contract period. When DSL broadband is available, the 4G modem provides a speed boost. When DSL is unavailable, the 4G modem provides a backup connection.  Using both products together will boost revenue by £288 (inc VAT) over the life of the initial contract period.


What about Fibre?

Fibre is being rolled out but this is going to take another 4-5 years and will never reach everyone. In the UK it is expected to take until the end of 2030 but nation-wide coverage in the UK means 99%. There will still be a need for interim solutions for several more years.



Hybrid speed boost will attract and retain customers for at least 24 months while the fibre rollout continues. Where FTTN remains the dominant technology, Tessares hybrid access solution can provide a cost effective differentiation in a crowded marketplace. 

Contact us for more information!

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