Limit # of simultaneous logins?

Question

Is it possible (or even practical) to try to do this?
My client wants *light* security on a series of pages, and
would like to
have two categories of passwords -
1. A single user, i.e., no simultaneous logins.
2. A group user, i.e., multiple simultaneous logins, up to
but not beyond,
some ceiling.
With PHP/MySQL is this feasible?
Murray --- ICQ 71997575
Adobe Community Expert
(If you *MUST* email me, don't LAUGH when you do so!)
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Answer 1

I can't speak for the PHP universe, but principles tend to
translate so I'll
take a shot anyway.
In ASP, you've got session_onstart and session_onend in your
global.asa
file. Obviously, if the user does not log out and just closes
the browser,
the session will remain active until it times out, but
session_onend will
run regardless of how the session is ended. The
session_onstart and
session_onend can be used to edit application variables
(which are truly
global and only fall out of scope when IIS is restarted). The
application
variable might, for instance, be named after the user ID and
contain the
number of current active sessions. Session_onstart is set to
create or
increment; session_onend is used to decrement.
In the case of a user closing the browser, you'd have a login
unavailable
until the session timeout is reached. Typically, explaining
this to users
is good enough and everyone understands that if they make a
mistake (or have
the computer crash or something), they may need to wait 20
minutes before
they're allowed to log in again (assuming you're using the
default 20 minute
timeout). As long as it's known up front and not a nasty
surprise, people
are generally understanding.
I don't think PHP has application variables, but you could do
the same with
a text file or a database table (with the bonus that a
database table can be
used to store session ID, login, logout, etc and give you all
kids of
history info). The crux of the matter is finding out if a PHP
application
has the equivalent of a global.asa and/or session_onstart and
session_onend
event handlers that are handled by the web server and not any
particular web
page. Sorry I can't be of more help there.
"Murray *ACE*" <[email protected]> wrote
in message
news:[email protected]...
> That was exactly what I told her.
>
> So - how would you approach this problem, then? One
solution is to
> monitor simultaneous logins, and that clearly is
impractical.
>
> How would you enable 'group' access if not this way?
>
> --
> Murray --- ICQ 71997575
> Adobe Community Expert
> (If you *MUST* email me, don't LAUGH when you do so!)
> ==================
>
http://www.dreamweavermx-templates.com
- Template Triage!
>
http://www.projectseven.com/go
- DW FAQs, Tutorials & Resources
>
http://www.dwfaq.com - DW FAQs,
Tutorials & Resources
>
http://www.macromedia.com/support/search/
- Macromedia (MM) Technotes
> ==================
>
>
> "Gary White" <[email protected]> wrote in
message
> news:[email protected]...
>> On Thu, 6 Sep 2007 10:38:10 -0400, "Murray *ACE*"
>> <[email protected]> wrote:
>>
>>>With PHP/MySQL is this feasible?
>>
>>
>> Not really. Because some users may simply close the
browser instead of
>> logging out, you have no reliable method to
determine who or how many
>> may still be logged in.
>>
>> Gary
>
>