The new Aastra Phone 312w is a wireless SIP phone compatible with WLAN infrastructure. It combines the openness of SIP with the many benefits of Voice over WLAN. For an enhanced productivity, the Aastra 312 offers to users the most popular telephony features of an office SIP phone while on the move on-site: call transfer, call forward, brokering, call waiting, hold, caller ID with name, do not disturb and call logs. It additionally offers a variety of convenient features such as a large back-lit graphic color display, hands-free operation, headset connector and a vibrating alert. A Memory-Card saves up to 100 phonebook entries, device-specific data and the MAC-address. When replacing the handset, a new registration is not necessary if the MEM-Card is transferred to the new device. Aastra Phone 312 supports large infrastructures and ease roll out scenarios by reading IP configurations and SIP specific configuration from DHCP options. Additionally it provides comfortable diagnostic functionality for service and maintenance.