Specifications

Configuring and Maintaining 400-Series IP Phones Overview
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Overview
ShoreTel 400-Series IP phones differ from other ShoreTel IP phones in that they use the Session
Initiation Protocol (SIP). While this difference requires administrators to use slightly modified
configuration and maintenance procedures, the 400-Series IP phones provide telephony features
similar to other ShoreTel IP phone models. Users who are familiar with other ShoreTel phone models
should have an easy transition to using the ShoreTel 400-Series IP phones.
This chapter provides details about configuring and maintaining the 400-Series IP phones.
All ShoreTel IP phones are supported by ShoreTel voice switches, which must have sufficient capacity
for all the phones in the system. IP endpoints are configured in the system with ShoreTel Director. For
more information on configuring ShoreTel 400-Series IP phones, see the ShoreTel Planning and
Installation Guide and the ShoreTel System Administration Guide.
IP Phone Failover
When IP phone failover is enabled on the IP Phone Options page in ShoreTel Director, if an IP phone
cannot communicate with its switch, the phone automatically connects to another switch at the same
site that has available configured IP phone resources. For IP phone failover to be effective, the system
must be planned with sufficient excess capacity to handle phones from at least one switch during a
failover event. For example, if a switch with 20 IP phone ports fails, 20 IP phone ports need to be
available elsewhere in the system.
Date and Time
ShoreTel 400-Series IP phones depend on a Network Time Protocol (NTP) server to authenticate a
secure connection and to provide the date and time to be displayed on for the phone’s screen. The
time displayed on the phone is the GMT value provided by the NTP server plus the offset from the time
zone setting of the phone. Users can set the time zone through the phone’s Options menu.
The IP address of the NTP server is delivered to the phone via DHCP or is manually configured in the
phone. In the absence of an accessible NTP server, the phone can obtain the time from its controlling
switch.
IP Phones and ShoreTel Voice Switches
ShoreTel voice switches provide configuration and call manager functionality for ShoreTel 400-Series
IP phones. Every site where IP phones are in use must have a ShoreTel voice switch configured to
support the number of IP phones at the site. SIP Proxy ports are not required for the ShoreTel 400-
Series IP phones.
ShoreTel voice switches provide configuration for the ShoreTel 400-Series phones in a different
manner than for other ShoreTel phone models. When a ShoreTel 400-Series IP phone downloads
configuration files during the bootup process it receives a list of all available switches. The phone then
randomly selects a switch from this list (starting with switches on the same subnet, if available) and
attempts to register with the switch.