A Study on Cost-Effective, High-Bandwidth Storage Architecture |
This paper describes the Network-Attached Secure Disk (NASD) storage architecture, prototype implementations of NAS Ddrives, array management for our architecture and three file systems built onour prototype. NASD provides scalable storage bandwidth without the cost ofservers used primarily for transferring data from peripheral networks e.g. SCSIto client networks e.g. ethernet. Increasing dataset sizes, new attachmenttechnologies, the convergence of peripheral and inter-processor switchednetworks, and the increased availability of on-drive transistors motivate andenable this new architecture. NASD is based on four main principles: directtransfer to clients, secure interfaces via cryptographic support, asynchronousnon-critical-path oversight, and variably-sized data objects. Measurements ofour prototype system show that these services can be cost effectivelyintegrated into a next generation disk drive ASIC. End-to-end measurements ofour prototype drive and file systems suggest that NASD can support conventionaldistributed file systems without performance degradation. More importantly, weshow scalable bandwidth for NASD-specialized file systems. Using a parallel data mining application, NASD drives deliver a linear scaling of 6.2 MB/s perclient drive pair, tested with up to eight pairs in our lab.