Portal Activity shows anonymous users

Hi All,

I have a question regarding the Portal Activity report. We are useing the report that is attached to the Solution Manager Diagnostics. This report provides a lot of important information. But one strange thing that I am not able to declare is the following:

The user overview is devided in two parts, the named users and the anonymous users. a few days in the week I see between 1 - 6 anonymous users. What does this mean? Does the really mean that users are accessing our portal without authentication?

I hope that someone can give us an answer on this question.

Thanks in advance,

Nico van der Linden...