Cisco IP phones as full-featured telephones can plug directly into your IP network. H.323 clients and CTI ports comprise software-based devices that you configure similarly to the Cisco IP phones. The Cisco CallManager allows you to configure phone features such as call forwarding and call waiting for your phone devices. You can also create phone button templates to assign a common button configuration to a large number of phones.
Once you have added the phones, you can associate users with them. By associating a user with a phone, you give that user control over that device.