Addis Hallmark

Addis Hallmark, CCNA, is a senior technical marketing engineer with Cisco Systems. He has been installing, configuring, administering, and troubleshooting the Cisco IP Telephony solution since the 2.3 release of CallManager. He has contributed to numerous design guides, application notes, and white papers on a variety of IP Telephony subjects, including CallManager, IP Phones, and IP gateways.