Kaleido services are modular building blocks for developing decentralized applications (Dapps). Each service focuses on a specific area of concerns. They work inside the context of a Kaleido environment. Some services make use of the blockchain in the environment, for instance the Token Swap service automatically deploys the Hash Timelock smart contract to the blockchain in order to provide the Atomic Swap functionality. Other services do not directly interact with the blockchain. For instance, the Interplanetary File System (IPFS) is a distributed peer-to-peer file system that does not rely on the blockchain at all nor does it communicate with the blockchain.
In terms of enterprise architectures, Kaleido services fit into various layers.
The layer closest to the client applications is the
B2B category of services. These are used directly by the client applications to perform operations that are completely off-chain.
The next layer is
Middleware. These services sit between the client application and the backend.
Blockchain First layer is comprised of services that work on top of the blockchain, or provide distributed services that work alongside the blockchain.
In terms of tenancy model, services can either be a single instance shared by all the members of the environment, or each member can provision multiple instances. The former type is called
Utility Services. The latter type is called
Services are protected by Application Credentials the same way as blockchain nodes. The same set of credentials can be used to access both the nodes and services.