Linksys WIP310 SPA500 Series and WIP310 IP Phone Administration Guide - Page 245

Cisco SPA 500 Series and Wireless IP Phone Field Reference Regional Tab B Parameter Referral Services Codes Description These codes tell the IP phone what to do when the user places the current call on hold and is listening to the second dial tone. One or more *code can be configured into this parameter, such as *98, or *97|*98|*123, etc. Max total length is 79 chars. This parameter applies when the user places the current call on hold (by Hook Flash) and is listening to second dial tone. Each *code (and the following valid target number according to current dial plan) entered on the second dial-tone triggers the IP phone to perform a blind transfer to a target number that is prepended by the service *code. For example, after the user dials *98, the IP phone plays a special dial tone called the Prompt Tone while waiting for the user the enter a target number (which is checked according to dial plan as in normal dialing). When a complete number is entered, the IP phone sends a blind REFER to the holding party with the Refer-To target equals to *98. This feature allows the IP phone to hand off a call to an application server to perform further processing, such as call park. The *codes should not conflict with any of the other vertical service codes internally processed by the IP phone. You can empty the corresponding *code that you do not want to IP phone to process. Cisco SPA 500 Series and WIP310 IP Phone Administration Guide 234