RtBrick Brings High Availability to Disaggregated Broadband Networks

This article was published in VMBlog on December 13, 2022. You can read the original article here  

RtBrick announced it has added high availability capabilities to its routing software to help re-establish network services with only minimal disruption. Broadband access is a critical resource, and it has become increasingly important to protect users from a fiber break or a hardware failure in the access network. The company's new capabilities add greater redundancy into networks to overcome these challenges and minimize the impact of the most severe network outages. 

RtBrick's software provides the Broadband Network Gateway (BNG) - the router that delivers internet services at the edge of a telco network - and is deployed on open hardware. In the event of a failure in the optical access network or a BNG hardware failure, which could affect tens of thousands of subscribers, services can now be re-established in a few seconds. 

RtBrick's software operates the control plane of both the primary BNG and a fully independent secondary BNG, maintaining it in a permanent state of readiness should there be a failure. The redundant system can be remotely located and used in a one-to-one configuration. 

"In essence, this follows a distributed Control and User Plane Separation (CUPS) approach," explains Hannes Gredler, CTO and Founder at RtBrick. "We have a distributed control plane located on individual switches, which is highly resilient and has no central point of failure, and then we allow it to control adjacent systems to create an extra layer of resilience." 

The redundant BNG shares state with the original, along with a live copy of routes, shapers, counters, and other subscriber information, enabling it to take over nearly instantaneously. 

"We can do this partly as a result of our ability to rewrite routes faster than conventional systems," added Gredler, "and partly because we can distribute and separate the control and user planes across multiple physical switches." 

RtBrick's BNG software has already been deployed in Deutsche Telekom's production broadband network and was recently selected by the TIP OpenBNG initiative, against criteria defined by five tier-1 carriers: BT, Deutsche Telekom, Telefonica, Telecom Italia Mobile and Vodafone.