1. Data Orgnization Frequently accessed data on the same storage device?
Conversely, all infrequently accessed data on the same storage device?
Retrieval efficiency through proper data placement
Load balancing and availability issues

2. Storage Manager
Allocation and storage of multimedia files on various storage devices (maintain metadata that maps logical blocks of files to physical blocks)
Enforce bandwidth reservations on storage devices to ensure that devices are not overloaded
Recover from hardware component failures
Coordinate data storage on several hierarchies

3. Frames to Storage Blocks
A one-to-one mapping between frames and blocks is inefficient
Partitioning a multimedia file (viewed as a stream of bytes) into fixed-size storage blocks
Extracting the frames from the storage blocks is left to the decoding software
Convert frame rate to average block delivery rate

4. Data Block Placement Retrieval Blocks Contiguous Placement
a single seek is enough (but fragmentation is a problem)
Scattered Placement
many intrafile seeks (can be alleviated using large block sizes and to read one block in each round)
Constrained Placement
intrafile seeks may be unavoidable if multiple blocks are needed in each round
reduce the seeks to a reasonable bound by bounding the separation of successive blocks

5. Data Striping RAID Scheme -- data is striped across each disk
achieves intrafile and interfile parallelism
Disk arrays are a good solution to the high bandwidth requirements of multimedia services

6. RAID Data striping for improved peformance
Redundancy for improved reliability
Data striping distributes data over multiple disks to make them appear as a single, fast, large disk
Multiple I/Os in parallel
multiple requests on separate disks (decreases queueing time seen by I/O requests)
single multiple block request on multiple disks (increases the effective transfer rate seen by a single request)