phranque - 7:08 am on Mar 8, 2013 (gmt 0)
PR might still be able to leak onto the external link if it's just Robots.txt'd.
iframes don't pass PR - only anchor elements (and if used properly link rel canonical elements)
that's because an iframe isn't considered a link between web resources.
#1 technically speaking, should an <iframe rel="nofollow" do the trick or no ?
i'm guessing the rel nofollow on an iframe won't validate but it's more useless and irrelevant than harmful.
#2 any assistance using robots.txt to exclude this particular iframe banner is appreciated. Just to give me an idea , so I could do the same with the others. I never knew you could block them through robots.txt Maybe ur just talking about the URL and not the whole iframe code? anyway, code below : <iframe width="300" scrolling="no" height="250" frameborder="0" src="http://ads.mysite.com/ads/juggcash_inserts/300x250_1_0_lp.php?nats=NDg0MDYwOjM6NDE" allowtransparency="true" marginheight="0" marginwidth="0" name="" rel="nofollow"> </iframe>
making some assumptions about your url structure - i would suggest blocking any access by googlebot to the ads.example.com hostname or at least the ads subirectory.
the robots exclusion protocol is pretty simple:
The Web Robots Pages:
Robots.txt Specifications - Webmasters — Google Developers:
Block or remove pages using a robots.txt file - Webmaster Tools Help:
note that robots.txt can and should exclude googlebot from crawling the (iframed) resource but G search may index the url without crawling the content...