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.
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
client.
Specify a list of domain name servers
available to the client.
Specify a list of MIT-LCS UDP servers
available to the client.
Specify the name of the client.
Specify the domain name that client should
use when resolving hostnames via DNS.
Specify the broadcast address in use on the
client's subnet.
Network Time
Protocol
Servers
Specify a list of NTP servers available to the
client by IP address.
Vendor-Specific
Information
Identify the vendor-specific information.
Identify the vendor type.
Identify a TFTP server when the 'sname' field
in the DHCP header has been used for DHCP
options.
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