HTML and CSS Reference
stored in the system. Depending on the publisher's specifications, the ad server will generate any of several different
tag types and formats, including the following:
Flash SWF tags
image and click tags
iframes are used to embed one htmL document inside another one.
For richer executions some publishers may require a file that lives on their servers; it allows the ad server to
communicate with the domain that the publisher's site is on. This is a requirement when “iframe busting” (an industry
term) is needed. Iframe busting allows an ad tag to render outside the publisher's desired iframe for the ad; this in turn
allows the ad server to interact directly with the publisher's content. This type of execution should be set up in advance
with the publisher to ensure that all parties are on the same page and that this file is in place at the time of ad serving.
Permission for this type of execution is usually granted only to trusted ad servers, as breaking the iframe creates the
ability to do damage if one wanted to. Figure 1-5 shows how an ad tag will treat iframes both “busted” and “non-busted”.
Figure 1-5. An ad tag can break free of an iframe when a publisher's hosted file is in place
Once the ad tags are generated and analyzed by the ad server, a final round of tracking quality assurance (QA) is run to
ensure that all the impressions are firing off and metrics are being accounted for. Assuming the tracking calls are good
to go, the unique tags are sent off to each and every publisher on the media plan. Upon receiving the tags, a publisher
will perform its own QA to ensure they operate smoothly with other site content in a live environment. It may take