"We've already seen instances where good-size enterprises had their VOIP infrastructures taken down by a worm." - Chris Thatcher, national practice leader at Dimension Data Holding.
The problem is, you see, there has been a lack of security in the design and development of VOIP. You would think that people would learn from mistakes of the past, but apparently not. Enterprises have, in general, been attracted to VOIP solutions because of such factors as price, extra features and so forth, but not security. And that is a big mistake. Therefore, itís entirely possible and indeed even pretty likely that VOIP systems will suffer problems of distributed denial-of-service, malicious code, spoofing and phishing. Now isn't that a cheery thought?