Yealink SIP-T54S, Administrator'S Manual

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Administrator’s Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
50
3.
Press or , or the
Switch
soft key to select the
Enabled
from the
Static DNS
field.
4.
Enter the desired value in the
Pri.DNS
and
Sec.DNS
field respectively.
5.
Press the
Save
soft key to accept the change.
A dialog box pops up to prompt that the settings will take effect after a reboot.
6.
Click
OK
to reboot the phone.
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 specific values in corresponding options.
The following table lists common DHCP options supported by IP phones.
Parameter DHCP Option Description
Subnet Mask 1 Specify the client’s subnet mask.
Time Offset 2
Specify the offset of the client's subnet in
seconds from Coordinated Universal Time (UTC).
Router 3
Specify a list of IP addresses for routers on the
client’s subnet.
Time Server 4
Specify a list of time servers available to the
client.
Domain Name
Server
6
Specify a list of domain name servers available to
the client.
Host Name 12 Specify the name of the client.
Domain Server 15
Specify the domain name that client should use
when resolving hostnames via DNS.
Network Time
Protocol Servers
42
Specify a list of NTP servers available to the client
by IP address.
Vendor-Specific
Information
43 Identify the vendor-specific information.
Vendor Class
Identifier
60 Identify the vendor type.
TFTP Server Name 66
Identify a TFTP server when the 'sname' field in
the DHCP header has been used for DHCP
options.