--- title: Software Components description: Every Ocean network is brought to life by many interacting symbiotic software components. --- Before reading this page, you should understand some [Ocean-specific terminology](/concepts/terminology/). ## Keeper A computer running an EVM-compatible blockchain client (such as [Parity Ethereum](https://www.parity.io/ethereum/)) where the associated blockchain network is running the Ocean Protocol [keeper-contracts](https://github.com/oceanprotocol/keeper-contracts) (smart contracts). See also: [Run a Keeper](/setup/keeper/) ## Secret Store A [Parity Secret Store](https://wiki.parity.io/Secret-Store): software for distributed key pair generation, distributed key storage, and threshold retrieval. It's used to store [asset](/concepts/terminology/#asset-or-data-asset) access-control keys. There are several clients for integrating the Parity Secret Store into Ocean: ## Aquarius Marketplaces run Aquarius to store and manage metadata about the [assets](/concepts/terminology/#asset-or-data-asset) available in their marketplace. It provides an HTTP API for interacting with an off-chain database (sometimes called "OceanDB"). ### OceanDB Drivers Aquarius supports several options for the off-chain database (OceanDB), including Elasticsearch and MongoDB. One can add support for another off-chain database by creating a new driver similar to the existing OceanDB drivers. Note: There is also a BigchainDB driver but it hasn't been maintained. ## Brizo Publishers run Brizo to manage interactions with marketplaces and consumers. It interacts with the publisher's cloud and/or on-premise infrastructure. The most basic scenario for a publisher is to provide access to the [assets](/concepts/terminology/#asset-or-data-asset) the publisher owns or manages, but [Brizo can do much more](/concepts/architecture/#brizo). ### Osmosis Drivers Brizo supports several options for file storage, including Azure Storage, Amazon S3 and on-premise storage. One can add support for another file storage option by creating a new driver similar to one of the existing Osmosis drivers. ## Squid Libraries Client libraries used by applications (such as Pleuston or Jupyter notebooks) to interact with Ocean components, including Keepers, Aquarius nodes, Brizo nodes, etc. ![How Squid is Used](images/ocean-squid-ecosystem.png) ## Pleuston An example marketplace/publisher front-end for developers to explore, download, and publish [assets](/concepts/terminology/#asset-or-data-asset) in an Ocean Protocol network. Implemented using [React](https://reactjs.org/) and [squid-js](https://github.com/oceanprotocol/squid-js). ## Commons Marketplace An online example marketplace/publisher for consumers to explore, download, and publish open data sets in the [Nile Testnet](/concepts/testnets/#the-nile-testnet). Implemented using [React](https://reactjs.org/) and [squid-js](https://github.com/oceanprotocol/squid-js). For more information, see [the blog post about Commons Marketplace](https://blog.oceanprotocol.com/the-commons-data-marketplace-c57a44288314).