Aastra Telecom C53I User Guide

Page of 602
IP Phone Models
1-2
41-001160-00, Rev 01  Release 2.0  
IP Phone Administrator Guide
Overview
IP Phone Models
Description
The IP Phone Models 53i, 55i, 57i, and 57i CT communicate over an IP network 
allowing you to receive and place calls in the same manner as a regular business 
telephone.
All phone models support the Session Initiation Protocol (SIP). The 57i CT offers 
the base phone along with a cordless extension.
References
For more information about the features and installation requirements, see the 
SIP IP Phone Installation Guide for your specific model..
The following illustration shows the types of IP Phone Models.
57i CT
12 Softkeys.
53i
3-Line LCD Display, 
(includes handset)
55i
6 Programmable Keys
3-Line LCD Display,
6 Programmable Keys,
6 Softkeys
57i
11-Line LCD Display,
12 Softkeys
15 Feature Keys on Handset