Blocking data for a good cause

By Scott Bradner
Network World, 06/07/99

When I get Internet service, I want full Internet service - but that's not what you get from some ISPs.

Some providers block or control their customers' abilities to use some protocols. This has been a bone of contention for us Internet purists for quite a while. But in some cases, blocking might just be reasonable.

One of the things that made the Internet what it is today is the freedom 'Net users have to experiment. With the Internet, most applications are run on a user's own computer. If you and I want to create an application and run it over the Internet, we can do just that. We do not need permission from ISPs, a government agency or phone company. Any blocking of data flows by ISPs limits this freedom.

But some ISPs insist on blocking some types of data. One thing many cable TV-based ISPs block is the set of protocols used by Windows for its "Net Neighborhood" feature. This makes a lot of sense because if this traffic is not blocked, you can peer into your neighbor's computer. (As a Mac user, this does not affect me one way or the other.)

A particularly galling type of blockage is one in which an ISP limits the ability of a user to send e-mail. In such a case, the ISP sets up a filter that only lets the user send e-mail to the ISP's message server. This is frequently done in the name of preventing unsolicited bulk e-mail, otherwise known as spam.

The ISP programs its message server to refuse to forward e-mail that is being sent to thousands of destinations or limits the amount of mail that an individual can send per day. This limits one's ability to use that ISP to distribute spam.

This sounds like a socially responsible thing to do, but it can be a real danger. All of the user's mail has to go through a server that the user does not control and one that records to whom the mail is sent. In addition, a dishonest ISP employee has a very easy place to eavesdrop on the mail.

AT&T WorldNet seems to have a better idea. The ISP puts this type of messaging restriction on new accounts, but the restriction can be removed after the account has been in place for awhile.

The normal way that a spamartist works is he uses a freetesting account, often with afalse name and credit card infor-mation, to send a batch of spam.The spammer then never uses the account again.

AT&T's model can stop this practice. By restricting bulk mailings for a certain time, AT&T can collect the account billing information it needs to track down customers in case they send spam at a later time. This messaging restriction is one with which I can live.

Disclaimer: Harvard does not restrict most things, such as ego. But the above is my support for some restrictions.