In this new neighborhood, much is different, including newthreats to the security and integrity of the machines we now depend on. At the root of the problem lie the increasing complexity of computer softwareand networks and the relative simplicity of the creatures that use them. Operating systems and applications have grown much more complicated as the usesand users of computers multiply. The software is often so convoluted that it isnot possible to insure that all bugs and vulnerabilities are out. Networks haveexposed a new problem, where individual operating systems are secure, butinsufficiencies in the protocols that connect them allow the machines to becompromised.
Automatic programs can surreptitiously test dictionaries against passwords until they are cracked.
The password written on a yellowsticky under the keyboard remains common vulnerability. Such problems are unfortunately amplified by some of the particular aspects ofthe network. Interoperability, the characteristic of the Internet that hasmade it so valuable, is at the same time its greatest vulnerability. Thatmachines are peers on the net means that any host can attempt to exploitsecurity weaknesses on any other system. In addition, the decentralized natureof the Internet provides neither the authority nor the tools to manage itsoperation.