Absolutely.  In practice, this is not that big of an issue but I was more commenting on this
As a potential situation.  I was serious about having someone standing over the shoulder anxiously
Awaiting the service to come back up.  That scenario was my first thought and it sucks when it happens
and the OP took my response as I had hoped.

“Hmmm, interesting thread, I will ask a few more questions and get a handle on how this will really
Go down in the real world.”

Thanks for everyone’s contributions to the thread.

Ed



On 5/19/10 8:29 PM, "Bryan O'Neal" <Bryan.ONeal@TheONealAndAssociates.com> wrote:

This is very true - but in practice this is not as common as you think. Our studies using DynDNS showed that Cox, Time Warner, Verizon, Qwest, Yahoo (Via dns change not ISP hosting),  and MegaPath did not cache, at least not more then a few min. I was unable to find anyone actually on AOL or EathLink or Comcast to test with. I did have a person on some small ISP like RoadRunner and they did cache.

Mind you our studies were not very scientific - call person we know on network have them hit site, change dns, have them hit site again. For some providers we only had one or two people using them. And for all the Yahoo based ISP's we just changed our primary DNS and tested ourselves. But, what we found supported our experience in that it was not a big issue.