ecp666

Hi Kerrie the Highway switch provides a speech path between 2 or more stack of an NEC large Pabx if you have a 4 pim single stack system you do not requierea Highway switch but if your system requieres more than 1500 ports say 1600-6000 max a high way switch provides the Voice path connections between the stacks so if its broke no voice comms will be possible between stacks .

IE extensions will not be able to talk to each other and trunks incomming /outgoing 1

Hope this helps JF