Data Storage Technology

The data storage and retrieval services utilized by the ECS services layer will be provided by both a Database Management System (DBMS) and a hierarchical le system (see Figure 2.1). The DBMS(s) will manage and provide access to structured data as well as certain types of unstructured data (e.g., text data), whereas the le system will provide direct access to the large data sets that will be produced and archived at the various DAACs 1. The focus of this chapter is on storage system hardware and software technology (DBMS technology is discussed in Chapter 3). The design and implementation of the data storage system is driven by the following requirements 18]: Large storage capacity { the ECS system is expected to archive approximately 2 Terabytes per day over a 15 year period. High data access rates { the storage system architecture has to be able to provide a sustained bandwidth of 100 Mbyte/sec. High data reliability { the system has to be designed to provide high data reliability and 1 These data sets may be organized into structured data by a higher level DBMS as in 7, 11].