Serve the ads in an Iframe and then block the iframe page from being indexed via robots.txt (so that it can't be cached). User views the page at Google in the cache, but calls your iframe page to grab a minty fresh ad.
js doc write will do too. Scope out some of the ad serving code by the big ad servers...
i'm probably being dumb here, or misunderstanding the point, but who would want to view google's cache?
it's not as if the page is likely to be viewed by anyone other than yourself so why bother going to the trouble of trying to stop google caching the page with an old ad on it?
I personally always look at googles cache before entering a site.
A) to many site's with slow servers I will always get good connection from google so I can quickly check if it's a site i want to goto or not without leaving the serps.
B) I also read somewhere that 70% - 80% of google users also check cache first.
wow, that blows me away. I really hadn't thought about the Google cache being used anywhere near that often. OK... so I actually thought it probably got next to no use.
Out of interest, what do you do if Google doesn't have a cached version? Do you go on to the site or pass it by?
I'm considering putting no cache tags on my site as I've got a lot of serious regular updating going on for the next few months, and cached shots just won't be relevant for any length of time.
I don't want to hijack Visit_Thailand post so he's want i have got.
I hardly ever go to a nocache site unless I'm doing SEO then I always check that site out fully ;)
We did a online test with four test sites in google we split the sites into two keyword phases.
site a blue widget parts cache position 3
site b blue widget parts no cache position 2
site c green widget parts cache position 1
site c green widget parts no cache position 3
we had 10% more clicks on the cached version.
we have used iframe to great succese also used ad folder to keep the banners in and didn't let google in there or cache
no, don't want to hijack either.. thought I might get away with a speed bump though :)
That's a very interesting result.. thank you!
I might have to consider that iframe option for a few selected spots myself.
Another option is to use .htaccess to block offsite referrals to those ad images or you could use mod_rewrite to replace those ads with "Advertise here!" images.
I always click the Google cache option first. It highlights the keywords I'm searching for.
I'm surprised at the 70% to 80% figure DaveN. Of the users who load images, the proportion on the few hundred sites I can monitor is very small.
vitplease's translation of the Very interesting French article on Google usage in France [webmasterworld.com] statses "use of cache: 0,6%".
I find the figure a little (ok a lot) high as well.
I think Brett made a post one time suggesting it was faster for many users to get from the cache. For those of us (probably most of us here) with broadband connections - it probably doesn't matter much.
Users use it now for the highlighting.
It's rare I actually visit sites anymore - I use the cache almost exclusively. Even on broadband, it's still faster.
another way to look at this is that the advertiser wasn't in google's cache when they started their advertising term so if they've paid for a years advertising they will have had a year on your site plus approximately a year in google's cache.
i think we need to remember that we all have a deep interest in search engines, particularly google, and know and use their features a LOT more than your average surfer ie we are not typical users, so the fact that we may use google's cache a lot of the time does not necessarily mean that everyone does. just my 2 pence worth!
So if you see a site with no cache on Google SERP do you visit it? I see that you have NOARCHIVE tag on your forum pages, is there a big downside to this or is this how most sites should be?
I'm pretty sure if you asked a typical surfer if he/she used Google's "cache", he/she would say, "their what??"
On one site, I implemented a cheap cgi-based ad rotation system a few months ago. I did it mainly to distribute ads and track performance, but it also makes sure even cache viewers get a new ad, and get counted.
I am using PhpAdsNew and haven't noticed that problem.
Thought you might want to know :)
Thank you everyone. I am also interested in answers to some of the questions which have come up.
Will have a look at iframes.
That's pretty much the case. I think there is somewhat of a downside to it, but not nearly the downside in allowing pages to be cached. It's the webmaster vs user differences in behavior again.
We are now experimenting with this no-cache tag. One of our sites pages is craled daily and usually carries the date tag on google.
Google has pretty much in 24 hours already removed (after adding the tag to the page) the cache, but I also see that the date has now been removed.
We have not lost SERP position but the lack of date when CNN above us one place and another site and all below have the date still (but they are all cached).
Is this normal ? Do you lose dates if you opt for no cache ?
"I also read somewhere that 70% - 80% of google users also check cache first"
Myth-dispelling time. DaveN, the vast majority of our users don't even realize what the cached link is. From the few times I've poked through our logs, I'd estimate that you're off by two full orders of magnitude. No offense, but 70-80% is completely off-base.