As a multi-protocol platform, Kaleido currently supports Enterprise Ethereum, Hyperledger Fabric and R3 Corda as protocol choices.
For Ethereum, there are three node client implementations to choose from for your permissioned blockchain: Geth, Quorum and Hyperledger Besu. Each client contains different protocol functionality (e.g. private transaction support) and configurable consensus implementations, allowing for individual networks to be built in accordance with consortia-level performance and privacy requirements.
For a deeper dive into the supported consensus algorithms, refer to the following blog post.
For Hyperledger Fabric, Kaleido provides a per-membership Fabric CA as the organization's trusted root, so that orderer and peer nodes in the membership can automatically get enrollment certificates issued via coordination flows orchestrated by the Kaleido platform. This makes it trivial to provision a multi-organization Fabric network. Other complex tasks such as creating channels and deploying chaincodes are also trivialized as simple button clicks or API calls.
For Corda, you can choose between OS (open source) and Enterprise. Both versions support 100% of the Corda protocol, so there are no real functional differences between the two. The differences are non-functional, with the Enterprise version offering more deployment flexibility to meet the needs of enterprise security standards, notary clusters and support for Hardware Security Modules (HSM).
For a detailed comparison, refer to the Corda documentation.