Tutorial on ISDN PRI Including 5ESS(R) Switch PRI and PRI Evolution

With the advent of ISDN and proliferation of advanced Customer Equipment (CPE) and introduction of services that use larger bandwidths such as video conferencing, a need had been created in the market place for switches that can switch bandwidths of up to 1536 Kbps. Large business customers are looking for ways to integrate their voice, data, and video applications in the same network with the flexibility of accessing various services offered by the Local Operating Companies (LECs) as well as Inter Exchage Carriers(IECs).