A PBX (Private Branch Exchange). Also known as a 'switch'. They have
various configurable algorithms for ring-down (i.e. routing calls to a
number of targets). It's probably easy to get one that would allow an
operator to punch in a 'not available' code, or with the right phone set
just push a 'not available' button.
You wouldn't want your operator to put someone on hold while they go for
a break, but that's a training issue.
If you just had 10 people and you didn't envision expanding you could
probably do this with a key system as well -- that's the kind of system
where the phone has one button ('key') for each line, and you push the
button for the line that's ringing to pick up. With a key system you
wouldn't have to have a 'bathroom break' code because the call would be
available to everyone. Key systems used to be quite different and less
expensive than PBXs, but these days the smarts are cheap and they are
looking more and more like each other -- so you probably pay by the line
no matter what.
If you're seriously considering this look in your yellow pages under
phone installers -- the better ones do this sort of stuff all the time
and will be able to guide you through the process.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
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