Installing Software has encountered a Error for Aptana plugin

when i install aptana plugin on eclipse,the detaile of the error is:

An error occurred while collecting items to be installed session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=). Unable to read repository at http://ift.tt/2jTgg7S. Connection reset

mine network is ok,this website i also could open,how can i solved it?