Cisco 7811

Network port (10/100 SW) connection.
IEEE 802.3af power enabled.
4DC adaptor port (DC48V).1
Access port (10/100 PC) connection
(optional).
5AC-to-DC power supply (optional).2
Handset connection.6AC power wall plug (optional).3
Cisco IP Phone 7811, 7821, 7841, and 7861 User Guide for Cisco Unified Communications Manager 10.0 (SIP)
2
Getting Started
Phone Connections