Jim to serve your 56k customers you will need to go digital( ISDN).I have heard that most ISP's are dumping the USR heat dragons and going to the portmaster solution. Since I will use such a limited few dial -in's I'll just camp on e-bay till I can accrue enough (3) isdn USR curriors to hook up to our Sonic Terminal Server. As a side point watch the wireless movement.It will make huge strides next year.
