Dhcp - Yealink SIP-T4X Administrator's Manual

Administrator's Guide for SIP-T4X IP Phones
T48G
This section describes how to configure basic network parameters for the IP phone.
Note
This section mainly introduces IPv4 network parameters. For more information on IPv6,
refer to IPv6 Support
DHCP (Dynamic Host Configuration Protocol) is a network protocol used to dynamically
allocate network parameters to network hosts. The automatic allocation of network
parameters to hosts eases the administrative burden of maintaining an IP network. IP
phones comply with the DHCP specifications documented in RFC 2131. If DHCP is used,
IP phones connected to the network become operational without having to be manually
assigned IP addresses and additional network parameters. Static DNS address(es) can
be configured and used when DHCP is enabled.
DHCP Option
DHCP provides a framework for passing information to TCP/IP network devices. Network
and other control information are carried in tagged data items that are stored in the
options field of the DHCP message. The data items themselves are also called options.
DHCP can be initiated by simply connecting the IP phone with the network. IP phones
broadcast DISCOVER messages to request the network information carried in DHCP
options, and the DHCP server responds with the specific values in the corresponding
options.
The following table lists the common DHCP options supported by IP phones.
Parameter
Subnet Mask
Time Offset
Router
Time Server
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DHCP Option
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Description
The default caller photo
Description
Specify the client's subnet mask.
Specify the offset of the client's subnet in
seconds from Coordinated Universal Time
(UTC).
Specify a list of IP addresses for routers on the
client's subnet.
Specify a list of time servers available to the