Apollo Server is a data acquisition software application designed to acquire continuous time series data, state of health data, triggers, and alerts from a wide range of remote Nanometrics field digitizers and SeedLink data sources. Packets are indexed to latitude-longitude coordinates, allowing the tracking of instrument changes and notification of users when changes are detected. This index also permits data to be recorded without the need to configure the central site to receive the data. Apollo Server is scalable and well suited for use in real-time networks ranging from small regional arrays to large national networks with hundreds of stations.
To ensure the continuous acquisition of data, Apollo Server uses an application error correction protocol that requests the re-transmission of any missing data. Data gaps are identified using both time and packet sequence numbers. The error correction protocol is robust and persistent and utilizes the full duration of the data storage media at each of the remote sites. The protocol operates on all data connections for all data types and is over and above any error correction provided by the underlying IP protocol.
The data acquired by Apollo Server is written to its online ring buffer Store in the publicly available Nanometrics Protocol (NP) data packet format. An NP packet requires a specific data header but the actual payload can be anything from Steim-compressed data to Extensible Markup Language (XML)/Resource Description Framework (RDF) or even photographic images. Each unique data type is described by RDF metadata that is stored in an NP packet or sequence of packets. Processes interacting with Apollo Server have access to the various data types as well as the metadata describing the data and packet formats.
In addition to the acquisition of data, Apollo Server can distribute data to any application that supports NP or SeedLink formats; such as Antares, NpToNmxp, Apollo Waveform, or another instance of Apollo Server, allowing a wide range of software applications to interface with the various data types.
Apollo Server is managed using a highly intuitive Web client that allows the completion of administrative tasks such as configuring the data retrievers and streamers, managing the Store, or shutting down the Web server.