Resilient PLC

Resilient PLC's image


Resilient PLC




  • Replace legacy billing system with robust real-time rating system
  • Provide a completely customized user portal
  • Implement within very short timeframe


  • jBilling


  • A billing system delivering accurate, high-volume call detail record processing
  • A very flexible charge model that can be adapted in an agile manner as new needs arise
  • A commercial billing system tailored—without compromise—to Resilient’s needs     

Resilient Deploys jBilling for Real-time Call Rating in Only Two Months

Resilient PLC is a pioneering provider of smart voice services to the largest and most challenging clients in the UK. Their customers—including banks and emergency services—rely on them for continuity and compliance in the event of business disruptions, as well as the agility to connect internal experts to address the needs of callers. More than 60% of global investment banks use Resilient’s cloud for carrying their inbound voice service, and Resilient carries more than 80% of calls to trading positions in the city of London. Additionally, 75% of global retail banks use Resilient’s cloud for incoming calls.


Having brought many successful products to market over the years, including Teamphone and smartnumbers, Resilient PLC continues to innovate. By introducing a new service characterized by real-time rating and billing, Resilient needed to know the current ratings and balance for any given account at any given moment. “We looked at a provider we had been using some time ago,” says Suresh Rasakulasuriar, Resilient’s VP, Development. “What we found is that they were very inflexible and could not meet our requirements for real-time billing. It was very difficult even to define our own tariff models, our way of architecting our products, and how we wanted to bill. It was very difficult to change anything.”

In addition to meeting the requirements for real-time charging and unique tariff models, Resilient PLC was also focussed on requirements for system availability. Every component involved in the delivery of their services needed to meet stringent criteria for robustness. Rasakulasuriar notes, “Our name says it all. We provide resilient services to our customers and we say to them: no matter what happens your calls won’t be lost. And in that way we were also looking at a solution where the provisioning, the management and indeed the billing would also be resilient—that we had an architecture that would never suffer from a single point of failure.”

As well, Resilient conveys its unique brand and associated value through a customized user interface. It also allows its resellers to brand their own interface for services they resell. This is a very important aspect of their product strategy and had to be supported by their billing infrastructure. “Having full control over the user interface is essential for us so we can provide the user experience we need,” comments Suresh.


jBilling was selected because, as the only open source enterprise-grade billing system, it could satisfy all of Resilient PLC’s demanding requirements. “jBilling’s Java-based technology was able to offer us those architectural implements to provide the scalable and resilient architecture we needed,” says Rasakulasuriar. “One of the things we explored in detail with jBilling in the early stages was to go through jBilling’s model for proving scalability and resilience; this was very important to us.”

​“We spent about a year and a half with a legacy provider and didn’t get anywhere. To jBilling’s credit, within a couple of months we had a solution up and running. So that kind of gives an indication of how inflexible the old solution was compared to jBilling.”

The project took only two months. First, jBilling worked alongside Resilient PLC’s technical team in a two week proof of concept, showing team members how to use jBilling’s robust plug-ins and API. Rasakulasuriar says, “When we had our two weeks of exploratory work with jBilling it soon became very clear that we had a lot of flexibility and a lot of power ‘under the hood’ to do what we wanted, and we made up our minds that this was the right way to go.”

Rasakulasuriar continues, “I found jBilling’s technical team very helpful, useful and responsive. We feel like the jBilling staff are part of our team, and that was pretty unique as with most vendors we work with we have a typical commercial relationship, and not a close working relationship like the one we have with jBilling.”

Resilient’s project required a completely customized UI designed to be fast and fit their operational model perfectly, therefore they made extensive use of jBilling’s API.


With jBilling deployed, Resilient PLC is benefiting in a number of key areas. jBilling’s mediation engine is processing call detail records in milliseconds per CDR, with the ability to scale even further with jBilling’s distributed cloud architecture.

jBiling is also meeting another key requirement: accurate rating of call detail records. Resilient had suspicions that they were under billing one of their largest revenue generators—a client making about a million calls per day. Rasakulasuriar says “we couldn’t validate with our older system. When we ran jBilling in parallel, we then began to see the losses.”

jBilling is also proving to be a time and money saver. Rasakulasuriar explains, “We know that jBilling is saving us money. We have fewer problems, fewer operational issues, and we’re saving heaps of time getting our requirements met.” 

Resilient PLC now has complete control and flexibility over their pricing models and how charges appear on customer invoices. With their previous system, they had difficulty modeling

“If we need to define additional rules or make changes we know we can go in easily and make those changes in timeframes that are very short. We’re talking about changes in an agile fashion—like days—whereas with the other providers we’d be speaking about months.”

some of their voice cloud services. Rasakulasuriar says “jBilling gives us the flexibility to build a number of models so that we can bill multi-line calls as a single call or separate legs of a call. It was quite difficult to do that using the non real-time mechanisms. jBilling’s real-time Java-based API allowed us to code this with ease.”

Resilient is now poised for the future. Rasakulasuriar continues, “We were able to build a very flexible generic charge model which means that we can define new products and new services without necessarily having to rewrite or change the billing system. We can do our work almost independently of jBilling and that separation is very useful and very important for us.”

“We had to have a billing solution customizable and tailored to our demands and needs. It was something that we found to be very difficult to find. With most of the systems we explored we found that we would need to retro-fit our requirements into their fixed structure. It was difficult and always a compromise, where with jBilling there is no compromise. jBilling gives us what we need.”

—Suresh Rasakulasuriar, VP Development, Resilient PLC