Hi,
Most browsers, and most servers, limit the number of simultaneous
requests between the same two endpoints. Usually that limit is two
requests at a time, although I've also seen it be just one. Some
browsers let the user configure it.
You can count on one (obvious -- well, to the extent you can count on
networks at all); more than that and all bets are off. This isn't at
the Prototype level, it's at the browser and server HTTP
implementation level.
HTH,
--
T.J. Crowder
Independent Software Consultant
tj / crowder software / com
www.crowdersoftware.com