NDS.Live: How we enable sharing data

In the second part of our article series on NDS.Live, we have established that NDS.Live breaks down map data into bite-sized chunks that can be easily and quickly shared, updated, and pieced together to form one precise model of the roads and their environment. This well-designed structure and granular categorization lay the foundation for a distributed ecosystem of map data providers.

The key advantage of an open standard like NDS.Live is that map data can be spread among different services, even originating from different suppliers. To make this work, NDS.Live is focused on service interfaces which deliver not only map data, but also all related information necessary to correctly filter and use it. The services implementing these interfaces may reside anywhere, in the car, in the cloud, etc. The format does not specify where and how exactly map data should be stored. Instead, it defines how it has to be delivered from one participant in the ecosystem to the other.

For this purpose, NDS.Live describes service interfaces using the schema language zserio, an open-source interface definition language. The schema defines the exact data layout of each request and response within the system. Thereby, interoperability on the interface level is reached. NDS.Live does not specify a physical storage format for the map data, such as a file format. It is left to each node in the NDS.Live ecosystem to persist data in a way that best suits its requirements, optimizing storage based on the environment it is running on (embedded, cloud, etc.). This gives map and traffic data providers an unprecedented amount of flexibility with regard to managing and deploying their data. Developers of navigation and HAD systems as well as carmakers enjoy the possibility to combine the best data sources into a solution that delivers an optimal driving experience to their clients. And last but not least, it carries forward the tradition of NDS’ interoperability – a major advantage over proprietary formats.

Sharing is caring: The internet of map data

Any networked system is made up of nodes, which provide connection endpoints from a client (e.g. a vehicle) perspective. Each endpoint is reachable under a certain physical address, under which a client may access an arbitrary service running on the node.

A trivial system might provide an infrastructure where each node is directly associated with a specific service. For example, there might be three nodes, one strictly serving map display data, another one for road network data, and a third one for live traffic data. However, this is not desirable for multiple reasons:

• Rigidity: A system like this is unable to handle nodes entering or leaving the network. This means that nodes cannot be added if network demand increases.
• Fragility: Clients have no useful means of reacting to downtime.
• Immutability: Changes to the service interface might break a clients’ ability to communicate with a node. Remote interfaces and exchanged data structure formats are effectively immutable as long as clients are supposed to use them.
• Vendor Monopoly: Fixed endpoints are typically served by a single vendor who carries responsibility for all aspects of the network.

NDS.Live is designed with opposite qualities in mind:

• Scalability: Nodes and services can dynamically enter and leave the network and be discovered by clients.
• Reliability: Service nodes are not responsible for the structural integrity of the network.
• Mutability: Map data formats can be developed and improved in a live system.
• Vendor Collaboration: Delegating responsibility for the structural aspects of the network allows vendors to focus on the quality of specific map use-cases.

Let’s look into some more details on how NDS.Live is taking up the challenge to achieve these qualities so that sharing data becomes easier. Among definitions of online electronic horizon, routing or search services, the following three concepts carry most of the load:

• First, Modules offer a semantic separation of concerns within the map standard. Development cycles of modules are decoupled, and vendors are able to rapidly iterate on specific aspects.
• Second, Service Registries are responsible for tracking the presence and state of service nodes in the network. Through this mechanism, the NDS.Live ecosystem becomes both scalable and more reliable.
• Third, SmartLayers allow services to freely combine data layers across modules and versions into singular deliverable data units that can be streamed over the network.

In this structure, you can recognize several principles known from the internet, such as the concept of registries or the modularization of content. Even more important is the ability to adapt to new sources of information, new kinds of content and new use cases. In our next blog article, we will discuss how exactly NDS.Live data employs modules, registries and SmartLayers to form a true internet of map data.