The Cisco 3845 Integrated Services Router provides the following support: - Wire-speed performance for concurrent services such as security and voice , and advanced services at full T3/E3 rates - Enhanced investment protection through increased performance and modularity - Enhanced investment protection through increased modularity - Increased density through High-Speed WAN Interface Card Slots (four) - Enhanced Network Module Slot - Support for over 90 existing and new modules - Support for majority of existing AIMs, NMs, WICs, VWICs, and VICs - Integrated GE ports with copper and fiber support - Optional Layer 2 switching support with Power over Ethernet (PoE) (as an option) , supports the 36-port Cisco EtherSwitch module (NMD-36ESW) Security : - On-board encryption - Support of up to 2500 VPN tunnels with the AIM-HPII-PLUS Module - Antivirus defense support through Network Admission Control (NAC) - Intrusion Prevention as well as stateful Cisco IOS Firewall support and many more essential security features Voice : - Analog and digital voice call support - Optional voice mail support - Optional support for Cisco CallManager Express for local call processing in stand alone business for up to 240 IP Phones - Optional support for Survivable Remote Site Telephony support for local call processing in small enterprise branch offices for up to 720 IP phones