Speaking at the Gartner Security Summit on Monday, Bob Gleichauf, the chief technology officer of Cisco's security technology group, said integrating Vista into a complex IT infrastructure could present problems.
"Parts of Vista scare me," said Gleichauf. "Anything with that level of systems complexity will have new threats, as well as bringing new solutions. It's always a struggle in security trying to build for what you don't know."
Gleichauf told ZDNet UK that Cisco views Vista both as a bearer of possible solutions to security problems, but also as a potential trigger of security issues.
"Vista will solve a lot of problems, but for every action, there's a reaction, and unforeseen side-effects and mutations. Networks can become more brittle unintentionally," said Gleichauf.
Systems complexity needs to be taken into consideration in any action plan for Vista implementation, he added.
"If you're embracing Vista it's not going to be 100 percent initially. It's going to create more heterogeneity for a while," said Gleichauf.
Analysts from Gartner have also found many businesses are nervous about integrating the security features of the upcoming operating system with legacy systems.
"Most organisations are cautious about Vista," said Eric Ouellet, vice president for research, security and privacy at Gartner. "[Companies] already have security tools, which are being built into Vista. The risk is to go to another system — there's always going to be some hits," Ouellet told ZDNet UK.
"The risk you have to manage is — is Microsoft going to get it right first time? Maybe yes, but are businesses going to take that risk?"
Microsoft has not helped to reassure customers by pushing back the release date of the OS and changing some of the promised features.
"People don't know what's coming down the pike," said Ouellet. "TPM is now not fully integrated — you can't rely on the feature and function set. Microsoft moving the goalposts is definitely adding to the heartburn."