On 27/03/2014 2:36, Charles Mills wrote:
On the mainframe side, I don't think I've ever seen an "automatic" 30-day trial, largely because "magic hidden files" are of course greatly frowned upon in this space. Mainframe 30-day trials in my experience require vendor administration to generate some sort of "30-day key."
The idea of "magic hidden files" might be frowned upon, but I think that is more due to the description. If you store data for use by your program in an obscure location, using standard, documented interfaces I don't see it as a problem. I worry more about software requiring authorized libraries and software that installs hooks into system services than software that might store a piece of data somewhere for its own use.
The difficlty is working out a location that would work on all customer systems. An idea might be something along the lines of storing a date and hash into the application load library on installation, then storing a hash of the hash somewhere in storage on first run so that if you reinstalled you also had to re-IPL (or find and delete the stored value).
The aim is not to create something foolproof and unhackable, it is really to remind the customer that they are supposed to be paying for the software, and make it at least inconvenient to bypass. PC 30 day trials are similar - you can probably use registry monitors etc. to find where the data is stored and delete it, and some people might do that, but the aim is to remind the honest customer to purchase.
I think the real reason most mainframe software requries you to contact the vendor for a trial is price. With high prices comes the assmption that a sales person will be involved (and vice versa - if a sales person is involved prices need to be set at a level that will support them!) The last thing sales people want is to have people interested in the software, but not know who they are. So the real reason for having to contact the vendor and request a key is to provide a lead for a sales person - not because of technical difficulties implementing a trial period.
Andrew Rowley -- and...@blackhillsoftware.com +61 413 302 386 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
