NASD Networking

Research has shown that the following issues are important for network-attached storage devices to be effective:

• A thin protocol stack
• Network support for small messages
• Cluster SAN support
• Workgroup LAN support
  
  

Drive-Side Network Processing

In order to deliver a high-bandwidth network interface, we have investgated two possible solutions for network-attached drives. Hardware-assisted protocol processing may provide cost-effective solutions for both high-bandwidth and low-latency. Rapid prototyping with reconfigurable logic allows us to investigate the effect of off-loading various aspects of protocol processing to specialized hardware. Our projections are that specialized hardware can be implemented using a very small amount of real-estate on a hard-drive ASIC, but speciallized hardware will provide significant performance advantages.

Client-Side Network Processing

Intelligent Fast Ethernet Network Interface Cards (NICs) are another potential solution for network performance. The intelligent network interface can off-load CPU intensive tasks from the host processor. Off-loading protocol processing, scatter-gather DMA operations, and packet fragmentation are a few of the tasks the network processor can perform. Intelligent network interfaces also can help to free-up main CPU bus bandwidth for use by the host processor.