SAS Expanders are a newer storage technology that lets you maximize the storage capability of your SAS controller card. Many SAS controllers support up to 128 hard drives. This can only be done with a SAS expander solution. Since many people are still unfamiliar with SAS Expansion, this site compares it to several storage technologies.

Why SAS Expanders?

• Single external multilane cable per enclosure.
• No adapters to convert internal ports to external.
• Can use the latest controllers and hard drives.

However, the key difference... what happens after the 12th, 16th or 24th drive?

• You can re-use your high-end, expander-enabled controller.

These charts show the pros & cons of expanders vs. other options:

• SAS Expanders vs. SAS (no expander)
• SAS Expanders vs. SATA Multilane
• SAS Expanders vs. Port Multipliers
• SAS Expanders vs. Everything

more: Frequently Asked Questions (FAQ)
more: Serial Attached SCSI (wikipedia.org)

How Much Do They Cost?

Q: Are SAS Expanders more expensive than other storage technologies?
A: The enclosures are a bit more expensive; you save on everything else.

In many cases, the costs are comparable with other storage technologies,
while giving you more in terms of simplicity, flexibility and futureproofing.

• Cost Comparison, Rackmount
• Cost Comparison, Tower

SAS Expander Enclosures are now available in Tower, 2U, 3U and 4U.