Cisco offers a wide variety of connectivity, expansion and upgrade modules to accommodate the range of application needs in customer networks. The network modules assure customers that they can choose a connectivity solution that fits their requirements. As modular components, they are easily and inexpensively field-upgradeable as customer requirements change.This DS5814 dial shelf contains fourteen slots that can accommodate line (trunk), modem and controller cards. There are 12 port T1, 12-port E1 and 1-port T3 line cards available. Up to four T1/E1 trunk cards or two T3 cards can be used simultaneously. 144 port modem cards are available, and up two controller cards for 1: 1 controller redundancy.