“They drew first blood, not me” – Rambo
British Telecom uses a Dynamic Line Management (DLM) system known as “RAMBo” to optimise broadband speeds for millions of customers. The company stopped using the system after a UK court ruled that it infringed two patents owned by ASSIA, a supplier of software solutions for broadband access networks.
To continue using RAMBo, BT would have been required to pay ASSIA a licence fee of £250,000 per week until it could modify the system to avoid infringing the patents. Rather than make those payments, BT discontinued the system on Friday 21 November.
BT maintains that removing RAMBo will “have no material effect on the operation or performance of our networks,” a claim disputed by ASSIA. The evidence below illustrates the practical benefits DLM systems can bring and the potential impact when they are switched off.
After DLM deployment, a range of studies and operational reports show that a significant percentage of lines experience increased speeds. In the examples cited, between 27% and 93% of lines achieved higher rates following DLM activation. Disabling the system is likely to reverse some of these gains and reduce overall throughput for affected customers.
Better line management also lowers the volume of customer support calls. Locations that adopted DLM reported reductions in support calls typically between 7% and 23%. With DLM disabled, call volumes are expected to rise, with projected increases in the range of 7.5% to 37%. That uplift would put additional pressure on customer service teams and could extend response times for other issues.
Similarly, fewer reported faults lead to fewer technician dispatches. After DLM was implemented, dispatches fell by between 10% and 30% in the surveyed deployments. Turning off DLM is expected to raise dispatch rates, with estimated increases between 11% and 49%. Higher dispatch rates mean more operational costs and longer wait times for customers who need on-site assistance.
Noah Messel, ASSIA’s Executive Vice President of Corporate Affairs & General Counsel, warned that discontinuing the NGA-DLM system would affect a significant number of BT customers. “Broadband services to businesses and homes will experience degradation of speed and reliability over time,” he said.
Messel added that DSL lines require ongoing management to maintain performance. “If DSLs are not managed, performance suffers over time, in some cases drastically. The support costs for those problem lines will almost certainly be more expensive than licensing ASSIA’s patents or software. We would be delighted to work with BT to deliver the best performance to businesses and homes in Britain.”
Update 10/12/14: BT provided the following response to this coverage:
“BT has been defending a claim brought by ASSIA since November 2011. They had asserted three patents against BT but during the proceedings, they had to narrow their allegations and withdraw one of these patents entirely.
In January 2014, the High Court found BT was infringing on only a minor part of one patent, and the Court of Appeal, whilst invalidating the majority of the claims of ASSIA’s other patent, ruled that BT’s network infringes what remains of the other patent.
Although BT was disappointed with the ruling, we have made minor changes to our programming which means these two decisions have no material effect on the operation or performance of our networks.”
The dispute highlights the tension between intellectual property rights and the operational needs of network providers. Patent holders argue that licensing fees protect innovation and allow them to continue developing software that improves network performance. Network operators, on the other hand, must weigh licensing costs against the practical effects on service, customer experience, and operational budgets.
When a DLM system like RAMBo is disabled, operators risk losing automated adjustments that proactively stabilise lines, reduce error rates, and optimise throughput. That may lead to gradual degradation on some lines, an increase in intermittent faults, and more customers reporting slow or unreliable connections. Over time, these trends can translate into higher support costs, increased technician visits, and lower customer satisfaction.
Conversely, operators sometimes choose to remove or redesign systems to avoid ongoing licence costs or to mitigate legal risk. In some cases, they may implement alternative solutions, make code changes to address the court’s findings, or rely on manual processes until a compliant automated system is available. BT’s statement suggests it believes the programming changes it implemented mitigate any material impact, but ASSIA and other observers remain sceptical.
Decisions like this also underline the importance of clear patent landscapes for critical network technologies. Service providers benefit from predictable licensing arrangements or open standards that allow them to deploy optimisations without unexpected legal exposure. Patent disputes can slow the adoption of beneficial technologies and create uncertainty for end users and providers alike.
The BT–ASSIA case is a practical example of how legal rulings can immediately affect network operations and customer experience. It poses a question for the industry about how best to balance intellectual property protection with the continued improvement of broadband services.
Do you think BT made the right decision to switch off their DLM solution? Let us know in the comments.