ARPA is a Secure Computation Network Compatible With Blockchains They propose a blockchain-based secure computation network of Multi-party Computation (MPC). ARPA cryptographically enables private smart contract, unprecedented data-at-use privacy protection, as well as scalable computational sharding.
DDK is a community platform that aims to create economic opportunities through the development of blockchain solutions. Since 2015, the DDK community claims to have contributed to a number of blockchain platforms.The DDK platform uses the Delegated Proof of Stake (DPoS) mechanism within its core. According to DDK, one of the advantages of a DPoS blockchain is that it depends on community members to participate in the maintenance and security of the platform so that each member’s participation provides benefit for all.