Yealink SIP-T48G - Page 89

Getting Started
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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.
Log Server
7
Specify a list of MIT-LCS UDP 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.
Broadcast
Address
28
Specify the broadcast address in use on the
client's subnet.
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.
Boot file Name
67
Identify a boot file when the 'file' field in the
DHCP header has been used for DHCP
options.
For more information on DHCP options, refer to
http://www.ietf.org/rfc/rfc2131.txt?number=2131 or