If you have lain awake at night wondering how much information about you is cruising round the Internet as you browse, read on — unless you are of a nervous disposition and one of those who know that They Are After You.
The information you release into the ether, all unaware, is comprehensive. Fortunately, perhaps, most Web servers do not bother to pick it up and record it in their log files. It is available, though, and some do record it, as these extracts show (taken from a log file supplied by a wilfully anonymous bod, who wanted to see what would happen if his very detailed log software was wound right up to its highest setting).
First the log file records the date, and a date with four digits in it, so the Web is Y2K-compliant. Then it notes the fact the caller was connected to Ihug (or whoever), on such-and-such a port number and such-and-such a socket number. Then the calling browser tells the server which file types it can accept, which probably gives a pretty fair idea of which applications are on the user’s machine. In this case it was ready to take MS-Word, MS-Excel and MS-Powerpoint.
After that it tells the server which Web site it was referred to it from, what the resolution of the user’s screen is, how many colours are being displayed, what type of CPU type is driving the user’s machine, which operating system is being used, and which browser it is (and what it is compatible with), even down to the detail of which version it is and whether it is a browser personalised for an ISP — if it was a copy of Netscape supplied by Xtra it would know that.
It also records which proxy the user is going through, and, if a search engine was being used, which one it was, and what search-string was entered.
Then it gets really nosy, and records the images that it sends down to the user, although whether there is enough detail to identify them precisely depends on what other data is being recorded. But it certainly knows what their file type was, and how big they were.
At least one niche-market browser even tells every server it meets what its user’s serial number and registration name is, which means that people who have that browser can never be anonymous. No, it is not Netscape or MSIE.
In short, you leave pretty clear fingerprints wherever you go. The detail is so comprehensive that taken together it should be enough to identify you. So if you are thinking of committing an Internet crime, think again. The chaps in blue shirts would have a fair chance of catching up with you — if the site where you committed the crime had a good log and had it running on full detail.