The unceremonious demise of Lockdown Networks last week is yet another sign that there are too many NAC vendors trying to sell to too few NAC customers.

Earlier signs include the demise of Caymas Systems and the ongoing transition Autonomic Networks is making as it leaves behind its former identity as NAC startup Vernier Networks.

The trouble these companies faced doesn’t mean NAC is a bad idea or that businesses shouldn’t buy NAC, but it does mean that they should be careful from whom they buy it if they want to have long-term support of the products.

Potential customers should add financial longevity to their list of criteria when checking out NAC vendors. Granted, this is tough to do and is outside the expertise of most people assigned to choosing a NAC vendor, but there are signs that can be researched.

These include probing the backgrounds of the team that is running the company to measure their track records. Or determining the quality and success rate of the financiers backing the company. Bad signs include not being able to point to a customer or two who can say what they think of the product and how well they are funded.

None of these is foolproof and evaluations of vendors should always include testing the gear and if it measures up, considering a purchase while giving weight to the business factors.

The fact is that in new technologies, the best work is usually done in some of the startups. Avoiding them simply because they are startups means losing out on perhaps buying the best of breed.

Tim Greene is senior editor at Network World.