IBM's BladeCenter HS20, for example, takes advantage of Seagate's new small form factor (SFF) 2.5" disk drives--up to two of them--for improved performance over IDE drives. The latest BladeCenter HS20 also has more I/O slots--up to eight Ethernet and four Fibre Channel (FC) port connections to each blade.

Hewlett-Packard's BladeSystem, meanwhile, will feature an integrated 4Gb/sec switch from FC networking vendor Brocade. The companies announced last month that a bladed version of Brocade's SilkWorm 4100 will be available for BladeSystem in the second quarter of 2005. According to Brocade, connecting to storage via an embedded FC switch can save upwards of 50% on connectivity costs because fewer ports and less cabling are used.

But FC isn't the only storage networking option for blade servers. Through a ...

InfiniBand on a blade has two advantages, says Stu Aaron, Topspin's VP of marketing and product management. InfiniBand provides more overall throughput than either Ethernet or FC (a single blade chassis can be outfitted with two four-port InfiniBand modules for 80Gb/sec of total throughput). Second, you reduce the number of adapters, switch ports and cables you need to achieve a given level of connectivity.

But is InfiniBand a valid option outside high-performance computing environments? Yes, Aaron says. More than 50% of Topspin's 10,000-plus port shipments last quarter were to enterprise environments, he says, while 30% of the firm's switches sold with Ethernet or FC gateway capabilities.