"Metering" Database Access on the Web

[Peter Murray]

I suspect you'll have to turn that question around to the database vendor
and ask how they want it enforced (or negotiate some sort of arrangement
with the vendor as part of the database license agreement).  You are right
that with session-based schemes such as "telnet" it was very easy to tell
when the patron was done with the database (either the patron logged out or
the session was idle for some period of time).  There are no such
indications on the web because the HTTP "session" lasts for only a few
seconds.  From there the patron can read the long document of the response
or jump immediately to somewhere else.

There are a few schemes one can dream up.  For instance, a popular library
automation vendor who does a lot of work in Ohio decides a "simultaneous
user" is a period of time after access from a particular IP address; when
another hit comes in from that IP address the time resets or the license is
freed after that set period of time.

If your database vendor is actually giving you a number of "passwords"
(e.g. HTTP basic authentication username/password combinations) to access
the database, I'd say you'd really have to talk with them to see how they
want it enforced.  You'd probably have to come up with some sort of proxy
scheme to hide the complexity of the different license passwords from the
user...


Good luck!

Peter

On Wed, 28 May 1997 16:28:10 -0700 hamilte at one.net (Elizabeth H. Hamilton)
wrote:

> Dear Web4lib List:
>
> One of the databases we subscribe to is going
> to a Web interface soon. This database allows
> us a specific number of passwords under our
> license.
>
> When all those are in concurrent use, no more
> people can access the database until someone
> is done with a password and no longer needs it.
>
> For session-based access such as telnet the
> process of checking for an available password
> and assigning it to the user for their session
> is not a problem. It is a process handled
> transparently behind the scenes. The user has
> no knowledge of it.
>
> How is this handled on the Web?
>
> Thank you in advance for your help!
>
>
> Elizabeth Hamilton
> University of Cincinnati Libraries
> elizabeth.hamilton at uc.edu
> hamilte at one.net

--
Peter Murray, Library Systems Manager                      pem at po.cwru.edu
Digital Media Services                   http://www.cwru.edu/home/pem.html
Case Western Reserve University, Cleveland, Ohio            W:216-368-5888