1 OASIS: Overlays and Active Services for Internetworked Storage Tal Lavian, Yin Li, George Porter, Mel Tsai, Randy H. Katz Computer Science Division Electrical Engineering and Computer Science Department University of California, Berkeley Berkeley, CA

2 Session Agenda Overview and Motivation: 5 Minutes (Randy) Active Services Testbed and Benchmarking: 30 Minutes (Mel) Open Research Issues in Storage Wide-Area Networking: 30 Minutes (George, Yin) Discussion (Randy)

3 Storage Networks Share storage among computers in complex, heterogeneous environments, with PCs, workstations, file servers, and mainframes Storage can be: –Direct attached (e.g., host bus adapter/HBA) –Network attached (via a file server) –Channel attached (primarily fibre channel, but also IBM SSA)

4 Storage Networks Workstation HI Cache Fibre Channel Loops Dual Ported Disks And Controllers HI DI Cache Crossbar Interconnect Mainframe Remote Storage Manager Fibre Channel Or ESCON Multiple Host Interconnections E.g, Hitachi, EMC, IBM Storage Arrays

5 Basic Attached Storage Device attached by SCSI HBA or channel interface Host manages the file-to-block mapping Host OS Disk Interface (DI) Allocation Table Disk, Cylinder,Track, Sector

6 Network-Attached Storage (NAS) aka Network File Service Mapping from File to Block done in network- attached File Server, not host LAN Host Network File Server OS Network Interface (NI) Network Interface (NI) Network Interface (NI) File Name, Offset, Length

7 Network-Attached Secure Devices (NASD) LAN Host Network File Server OS Network Interface (NI) Network Interface (NI) Network Interface (NI) Network-attached Secure Device (NASD) OS File Name, Offset, Length Disk, Cylinder, Track, Sector Research project on device embedded protocol stack, authentication

8 Storage Platforms “Storage Virtualization” Disk Storage Subsystem Work Station Main Frame Main Frame Channel Interface OS LUN, Offset, Length LUN To PHY LUN = Logical Unit Logical disk mapping onto underlying physical disks on logical block to physical block basis

9 LAN Host Network Interface (NI) Network Interface (NI) Network Interface (NI) File Name, Offset, Length File Server File Server File Server NAS NAS distinguished by an exported Network File System interface over a standard Local Area Network-based transport

10 Optical Disk Storage Subsystem SAN Main Frame Disk Storage Subsystem Tape Storage Subsystem Channel Interface LAN Host Network Interface (NI) Network Interface (NI) Network Interface (NI) File Name, Offset, Length File Server File Server File Server CI LUN, Offset, Length Main Frame CI LUN, Offset, Length PHY Device, Cyl, Trk, Sector NAS + SAN SAN distinguished by a block-oriented interface; Usually implemented across a channel-oriented fabric

11 Optical Disk Storage Subsystem SAN Main Frame Disk Storage Subsystem Tape Storage Subsystem Channel Interface LAN Host Network Interface (NI) Network Interface (NI) Network Interface (NI) File Name, Offset, Length File Server File Server File Server CI LUN, Offset, Length Gate way WAN Gate way LAN SAN Main Frame FS DSS Remote SAN CI LUN, Offset, Length PHY Device, Cyl, Trk, Sector NAS + SAN + SWAN Now extend the NAS or the SAN over a wide-area network transport … NOTE: wide-area SAN is new idea

12 Research Agenda Storage access as a composed service Datacenter disaster response –Low latency establishment of high speed connectivity –Rapid copying of huge data volumes to remote sites as quickly as possible »Rapid identification of possible off-load sites »Exploitation of geographic & topological diversity of connectivity »Harness parallelism in data copying operation –Understand the role of “in the network” programmability to implement virtualization and server-less processing –Prototype on top of PlanetLab