“The problem with PCs infected with bots has stymied security professionals ever since botnets came into wide use among cyber criminals. Attempts to shut down the command-and-control servers only temporarily have any effect, and investigators take months — or years — to nab the those responsible for the attacks.
Now Microsoft is arguing that the security community needs to develop a collective health policy to restrict sick PCs — those infected with malware — from connecting to the Internet.”
(Microsoft: Ban ‘sick’ PCs from the Internet | Malware – InfoWorld)