Aastra Telecom SIP 57I - Manual (Page 20)

IP Phone Models
1-2 41-001160-00, Release 2.1, Rev 04
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.
53i
55i
57i 57i CT