Blade servers have been touted for some time as a solution that can improve server management and cut costs, and organisations are increasingly calling on blade technology to deliver on those promises. To meet the growing demand for such products, all of the big players -- including IBM, Dell, and Compaq -- have stepped into the arena and introduced blade server lines. Many organisations have held back on making the jump to blade technology, however. Some simply haven't had the budgets to make the investment or had already invested in different technologies before blades became widely available. Others may still be unconvinced of the potential benefits of blade technology. I'll give you some details about what blades are, how they achieve cost savings, and how they streamline management. By examining this solution from the vantage point of someone who has deployed it, I may help you decide if blade servers would be a valuable investment for your organisation. What's so great about blades? The term 'blade' refers to how thin the servers are. Blades resemble PC add-in cards rather than full-fledged servers. And, in fact, blades really aren't full servers until they're plugged into the enclosures. Organisations are realising benefits from blade servers in three key areas:

• Reduced space requirements
• Reduced energy consumption
• Improved server management

Blade servers will be most welcomed in large data centers where smaller space requirements and reduced energy consumption can translate directly into lower operating costs. The basic idea behind blade servers is consolidation. By allowing servers to share resources provided by a single chassis -- such as network connections, power, and cooling fans -- the individual servers can be made much more compact. Just the CPUs, drives, and memory, for example, can be housed on a single blade. The design essentially allows you to cram a lot more processing power into a smaller space. In terms of hardware, two components comprise the blade server solution: the blades themselves and the enclosures that house them. The enclosures essentially connect the blades installed to the shared resources, and you can configure the enclosures according to your needs. Because of this consolidation, a chassis can house a dozen or more servers. Vendors make various claims about how many blades can actually fit into a single enclosure -- some say as many as 30 -- but this is highly variable depending on the functionality put into the enclosure. Quadrix Solutions CTO Tom Palmieri says that data center density is a key benefit blades offer. And the processing power density comes at a lower cost in terms of energy used. 'You can get three times more servers in a cabinet than you'd normally be able to," said Palmieri, "and you can basically use approximately half the power of what the whole cabinet filled with 1U (unit) servers would use.' Because the enclosure supplies functions that servers would normally house individually in each box, the blades are equipped with the bare necessities. 'The blades don't have a lot of the circuitry a full-fledged motherboard needs to have,' said Palmieri. 'So you don't have duplicates of the same equipment in cases where it's a waste to do so.' The scaling down of what's installed on the blade is part of the reason they're more economical in terms of space and power consumed. Instead of having 12 different servers, each with its own power supply, you now have 12 servers housed in one box with one power supply. Palmieri said an important factor to consider is that sufficient power must be supplied to the multiple CPUs. The end result is that an enclosure with multiple blades consumes less power than the same number of standalone servers.