BNG - Broadband Network Gateway

Over recent years, ‘cloud-native’ service providers have developed ways to build and run massive data centers with a high degree of automation, to reduce operational overheads and deliver levels of service agility beyond traditional carrier infrastructure. RtBrick’s open BNG brings these same benefits to carrier access networks, by disaggregating software from hardware and applying the same battle-hardened DevOps cloud automation tools that have been adopted by the world’s biggest cloud providers. 

The RtBrick BNG is delivered as a software container, running on the Open Network Linux (ONL) provided by the hardware SKU manufacturers, which handles peripherals such as LEDs, temperature sensors, and so on.

The RtBrick BNG software runs on low-cost but powerful open switches as an open BNG. It can scale down as well as up, but selecting the best open switch for your use-case.

Benefits

RtBrick’s open BNG software delivers some significant benefits compared to traditional monolithic systems:

Greater Agility

Pick your optimum hardware to deliver the same services from small temperature hardened switches as from large multi-terabit-per-second devices.

With ‘cloud-native’ operations you can add capacity, or roll-out new service features, in a matter of minutes instead of days or weeks. The software itself is developed using Agile methodologies so that features are rapidly prototyped and implemented, reducing the time-to-market for new services. Control everything through open APIs, and benefit from our in-built Prometheus time-series-database for telemetry.

Reduced risk

Stateful high availability allows IPoE subscribers to be re-established without them even noticing a failure. And benefit from the world’s fastest routing convergence times. 

RtBrick’s BNG software has an order of magnitude fewer lines of code than traditional routers, and a single state database rather than hundreds. The whole system is less complex, less prone to bugs and has much faster restart times. It also allows you to pick and mix between the latest silicon and the best available software. By using open switches, you can also diversify your hardware supply chain if you need to.

Lower cost-levels

RtBrick's software runs on powerful but low-cost open switches, with lower power consumed per gigabit than traditional routers.

Deployment at Smaller Scale

For small to medium deployments, and a highly distributed architecture, all BNG functionality can be operated on a single low-cost open switch, which can also operate as a Multiservice Edge Router. The software image running on the single switch includes all of the service-facing features and the core routing features in the same platform. It is very economical where there are lower concentrations of subscribers and can also run on smaller form-factor hardware, that is hardened for deployments in cabinets or cell-sites. 

Multiservice Edge Router on a single switch

The ability to highly distribute the BNG deeper into the network also enables services to be terminated closer to compute and storage that is located closer to consumers.

Deployment at High Scale

The BNG’s subscriber management capacity can also be provided in a scale-out architecture called the Point-Of-Deployment (PoD), also known as a SEBA PoD (SDN Enabled PoD). A large-scale PoD consists of Access Leaf Routers aggregated by a layer of Spine Leaf Routers in an auto-provisioned CLOS topology. The Access Leaves deliver subscriber management functionality. For even greater scalability a layer of Border Leaves can be added to provide more connectivity to the core of the provider network.

Disaggregated Multiservice Edge Router at Very Large ScaleThe leaves can be scaled out horizontally to increase the number of subscribers supported on the PoD, providing a pay-as-you-grow architecture. PPPoE Subscribers can be terminated on the Access Leaf Routers or tunneled to an LNS over L2TPv2. L2 Cross Connect (L2X) allows subscriber traffic to be tunnelled out of the PoD at Layer 2, providing wholesale connectivity.

Legacy Services

Our Open BNG software can deliver most of your complex broadband services, with HQoS schemes and IPTV support, for example. But you can also re-use your existing infrastructure to continue to provide lower volume legacy services, and optimize the rest of the network for the bulk of your traffic - providing large volumes of high bandwidth services at a lower cost-point with a web-scale operating environment. So your RtBrick BNG can act as a service cross-connect, routing each subscriber to the appropriate network infrastructure and extending the life of your high-cost legacy BRAS or BNG systems, for example.

Management and Operations

Along with a traditional CLI, RtBrick’s Management API has been designed to simplify the integration with your existing OSS and BSS systems. It reduces the amount of time and effort required to make your disaggregated network operational, and it leverages widely-adopted industry tools and programming languages. RtBrick’s API is ‘consumer-driven’ – which means you can use the formats and languages of your choice, rather than have them imposed on you by a vendor. This allows you to build a client in Python, Go or Java, for example, as you prefer. And the APIs are all edited in Swagger, which is also a widely understood tool used by developers. RtBrick’s Management API actually comprises of several underlying APIs, which each follow the same consumer-driven approach.

Features and Options

The features supported by RtBrick FullStack are expanding all the time, because it's much faster for us to add and test new features than it is using a traditional monolithic code base. You can see our current feature list on our latest data sheet.

RtBrick's BNG is licensed per subscriber on a network-wide basis (in additional to a base license for each physical switch). There is a choice between Essentials and Benefits licenses. The Benefits license includes High Availability features and support for multiple queues per subscriber.

CGNAT licenses can also be added per subscriber. 

Example: Deutsche Telekom's next generation access project

Deutsche Telekom is a good example of a carrier looking to benefit from a disaggregated access network, with their Access 4.0 project. 

“The focus is on having a more open, more flexible solution. The whole story is about disaggregation of hardware and software. RtBrick brings a piece of software that sits on the switches. They have built software that can program Broadcom chips, so they do the full BNG function.” Robert Soukup, DT’s senior program manager for Access 4.0 (quoted in an interview with FierceTelecom, March 2019)

Compatible Hardware

RtBrick's Full Stack routing software can operate on many bare metal switches, depending on your performance and port count requirements. You can find details of compatible hardware here.