A recent links scheme I came across seems to be a network to exchange links between member sites, IMO, not only is it a terribly obvious link scheme, but it appears a dangerous one too.

It works on the "transient link" system, every time you refresh a page, the links change.

On top of this, the pages you link to can come from anywhere, there does seem to be a minimum PR requirement, and no drugs/porn/gambling, but apart from that, no quality control system seems in evidence.

With the recent thread on the dangers of linking to "bad neighbourhoods" I'd advise anyone tempted to join such a network, to be extra cautious.

http://forums.searchenginewatch.com/showthread.php?t=3279

Thanks for not referencing specifics glengara, as it's the principles that are necessary for productive discussion; and we won't be needing specifics downstream in the thread, either.

It works on the "transient link" system, every time you refresh a page, the links change.
Right - there's a rotation and whatever is there at the time of the page being crawled is what gets picked up as a backlink.

The first time I encountered that was with a client site that showed some backlinks from PR6 pages on a site. There was nothing dodgy being done, as I later found out - but I went hunting because when I looked I saw no link to the client's site at all.

What it was, was rotating banners that just didn't happen to be there when I happened to look, which was a number of times. On topic, perfectly legit advertising on a site with a related subject area - and this was before the onslaught of buying links for PR, something which the linking site would not be inclined to participate in anyway.

I'm assuming it works on the same random rotation principle, and that the crawlers pick up whatever is on the page at that moment. The difference lies in the composition of the participants and the "organization" of the thing, so to speak.

"I'm assuming it works on the same random rotation principle, and that the crawlers pick up whatever is on the page at that moment."

You're probably right (I am only reading the description and not looking at whatever site you guys are talking about). This is actually used legitimately a lot in the blogosphere and within many webrings.

In those instances, the crawlers do indeed pick up the links on the page at the moment they arrive. However, if the site they're listed on is a frequently crawled site, the links won't be around long enough to give you any type of sustained boost.

Some bloggers don't want the list of all 200 blogs they link to showing on their sidebar and making the page take forever to load, so they randomize a list of say 5-10 blogs to show on the main page with a link to the full list. This script is actually provided by most of the bigger blog design firms as an add on and I've seen it being used more and more.

Webrings also have the feature - they show five member sites of the ring in addition to the webring code, if the site owner so chooses to use that version of the code.

Seems stupid to use as a "link exchange" scheme to me - because your link would appear and disappear - not really providing much "staying benefit" with your ranks.