Blockchain and Tangle are data structures and protocols used to create an immutable public record of data ensured by a network of peer-to-peer participants that maintain a monotonic constantly growing set of data records known as ledgers. Both technologies provide a decentralized solution that guarantees the exchange, among billions of IoT devices, of large amounts of trusted messages, which are very valuable as long as they are valid and complete. This highly encrypted and secure peer-to-peer messaging mechanism is adopted in this project to manage the processing of IoT transactions. To maintain transactions private, and secured consensus algorithms are responsible for validating and choosing transactions and recording them in the global ledger. The results showed that the speed of the consensus algorithms can affect the creation in real-time of reliable stories that track the events of the IoT networks. After incorporating Complex Event Processing that allows selecting only those high-level events, it is possible to obtain an improvement in many situations. The result is a Middleware system that provides a framework for the construction of large-scale computer applications that use Complex Events Processing and different decentralized ledgers such as the blockchain of Ethereum or IOTA Tangle, for secure data storage.