The Cisco Channelized T1/E1 & ISDN PRI High-Speed WAN Modules combine multiple T1/E1 WAN connectivity-Channelized T1/E1 & ISDN Primary Rate Interface (PRI), in the same card. With flexible WAN connectivity options, together with integrated routing, security, voice, & wireless capabilities, Cisco Integrated Services Routers can meet every need of enterprise-class branch offices today & in the future. The integrated channel service unit/data service unit (CSU/DSU) function allows customers to consolidate customer premises equipment (CPE). The 1- & 2-port Channelized T1/E1 & ISDN PRI HWICs are updated versions of the E1/T1 ISDN PRI network modules, with the same functions & performance in a compact form factor of HWIC. You can save the network module slots for other LAN/WAN connectivity, & your deployment flexibility is greatly enhanced.