On Tue, 17 Feb 2004, Tony Hain wrote: : Most of the responses to the anti-spam thread, and the comments to Itojun's : IAB presentation in Miami about filtering, show that this community has been : thoroughly infiltrated and is now as CLUELESS as the PSTN providers, and : just as power hungry. The current ISPs have the opportunity to turn the : Internet into the PSTN, where customers can have any service they want as : long as it uses an audio interface and a rotary dial for signaling. ;) Filtering, however, tends to be used to stave off real problems with the use of the service. POTS lines on modern switches will drop voltage to a trickle, for instance, if a device on the customer's end causes intermittent partial shorts or rapidly cycles through off-hook state. So, in making the PSTN analogy, I'd have to say that filtering an application -- based on a trigger -- would be perfectly acceptable for an ISP to do. Mind you, this assessment does not have any relevance to blanket blocking. It only addresses filtering on a trigger basis, which is performed by some residential service providers today. (I personally feel that blanket blocking particularly vulnerable things like NetBIOS, because we can't get the vendor in question to fix the glaring problems on a timely basis and work to prevent future ones, is a benefit to the Internet as a whole. But protocols that don't involve completely broken and security-risking service implementations, such as SMTP itself, don't warrant blanket blocking in my opinion.) -- -- Todd Vierling <tv@duh.org> <tv@pobox.com>